While Civ IV definitely is a game that favours the skilled player, there are some issues I definitely feel should not have to be part of your mindset, issues that work counter to intuitive playing.
Now I'm discussing tips and techniques that brings you from winning single-player games comfortably on Noble to being able to win at Monarch or Emperor; not pure newb stuff.
Some of you may even like things how they are. Please don't turn this thread into "don't change anything". Instead imagine that all the changes I'm discussing can be turned off with a switch.
My main point is that Civ forces you, the player, to keep track of things the computer rightfully should do itself. The realization that you can't escape the micromanagement if you want to improve your play beyond Noble (circa) is a definite turn-off for me.
PRE-CHOPPING
Do your Settlers take tens of turns to complete while your city doesn't grow?
Then you don't pre-chop your forests, and only then switch to a Settler build. In just one or a few turns later your Workers can complete several chops, thus producing the Settler, and allowing the city to get back to growing.
This isn't intuitive in that it goes counter to what the game says "building settlers halt growth".
It requires careful micromanagement (you wouldn't want your Worker to accidentally finish a chop before you're ready to switch to the Settler build).
The automatic settlers don't do it, which hints at an exploit.
But it is definitely useful, and so you'll feel forced to use it to compete.
Solution 1: If a Worker chops a forest in 5 turns for 50 hammers, then instead it should yield 10 hammers each turn.
This levels the field between casual players (and AIs I suspect) and obsessive perfectionists (i.e. good Civ players).
Solution 2: If Firaxis doesn't like the rather significant change this brings (in that you can no longer avoid no-growth turns unless you have loads of Workers) then the auto-workers should know about prechopping and use it.
WORKER-STEALING
I've got the impression good Civ players build very few Workers. Instead, they steal them from AIs.
I can't imagine this is "working as intended", and so:
Solution: Make AI Workers always consider enemy units to be hostile, except when you simply cannot declare war, and perhaps when the AI has decided to sneak attack the enemy civ anyway (and thus "wants" war). If the AI decides the Worker can't or won't move away, it should escort its workers!
The AI should especially take into consideration special abilities - such as a Woodsman II promoted Warrior, that can move two steps.
QUEUCHA RUSH
This isn't just about the Queucha unit, but in general.
Solution: The AI simply must take into account special vulnerabilities when deciding whether it's city defense is strong enough. For instance, it's exploitatively easy to attack Archers with Quechuas and Axemen with Chariots*. The AI should whip a single Warrior and Archer respectively in these cases, at least making the rush tactic harder than stealing candy from babes.
THE NO-DEFENSE CITY DEFENSE
Civ armies are generally stronger on attack than defense, despite the bonuses given for fortification, city walls, etc.
This is especially true for city combat.
So when faced with a huge stack (that has various units and no obvious weakness; and contains plenty of siege units too) what do you do: reinforce the city, massing your defenders?
No! What you do is retreat one step outside the city. The AI will fall for the trap and take the city, moving in his entire stack.
Now your siege units are right next to a city with no fortified units and zero defense!
This means you can attack, and your catapults (or artillery) will reduce his entire stack to minimal strength. Then it's a simple matter of mopping up, giving massive xp and probably a Great General too.
This way a stack can hold a front indefinitely even when facing several stacks that are each larger than your own.
This also means that once you've reached a certain minimum number of attack units, it makes sense to only build siege units thereafter.
This exploits the AI, and generally makes war into something strange with no basis in real life.
Solution 1: Redesign combat so newly taken cities aren't the death trap they are now.
BEING BEAT TO WONDERS
Yes, you can start building a wonder without any intention whatsoever to finish it. You're after the cash you get when an AI builds it instead. This allows you to run at 100% science for quite a while.
I suspect you simply get too much cash compared to the effort. Which may be less than perhaps the designers though, considering the 50% discount you get when you have the specified resource.
The original idea, to get a consolation gift when you're beat to an important Wonder, was perhaps a little too naive...?
Solution: I see no other solution than to reduce the amount of consolation cash. You should certainly not be able to get more cash than if the city produced 100% wealth for all those wonder-building turns (irrespective of Industrious and resource access).
UNIT QUEUES AND CIVIC CHANGES
Don't get me wrong, being able to order a city to build more than one thing at a time, as well as ordering "infinite builds" is nice, and definitely something to keep.
But good Civ players know better than using this queue only for convenience. Somewhat like pre-chopping, you can build a military unit to one round short of completion, then a second one, then a third one. This enables you to switch to warlike civics (Vasselage, Theocracy) just for a few turns while all those units pour out of the gates, getting those juicy xp, without having to endure those same civics for all the time it really takes to build those units.
After all, civics good for the military aren't the best for commerce and research.
And thus we have yet another way of getting to have the cake and eat it too...
Solution: Again, absolutes need to be removed from the game. You can't get the xp bonus at the end of production, the game must calculate what each turn of production yields (a fraction of a single xp) and then assign that, turn for turn.
Again, the reason for this change is to make micromanagement not worthwhile. Or, in other terms, make it so a good Civ player doesn't feel forced to use "techniques" like in this post just to be able to compete, as they make a game drag out while you're obsessing with details.
GENERAL MICROMANAGEMENT
As it is, micromanagement pays for itself. That is, you must do it, or resign yourself to playing at lower levels of difficulty. The only way to reduce this in the next version of Civ is by making it not worthwhile.
First and foremost, the game must be made aware of things like CE (Cottage Economy) and SE (Specialist Economy).
You must be able to tell your Workers "this city is running a CE, so DON'T BUILD ANY STUPID FARMS".
You must be able to tell your Workers "this city is running a SE, so BUILD ONLY FARMS".
FRACTIONAL RESEARCH
Apparently the way Civ uses whole integer arithmetic you stand to lose quite a lot of research of you set your science rate to less than 100% (once you have Libraries, Observatories etc online).
A true Civ expert would instead keep switching between 0% science and 100% science: full throttle until you run out of money, and then 0% to fill your coffers instead. This cumbersome way of doing it avoids losing fractional amounts, which saves you a lot of turns on research over the course of a long game.
And that's not even considering fringe benefits of stopping research for a while, such as getting bonuses for not being the tech leader in certain circumstances.
(And yes, I'm ignoring the Specialist Economy for the moment)
Solution: None other than using fractions in calculations. Of course setting your research to 70% for ten turns should give identical results to running at 0% for three turns and then going to 100%! Anything else is absurd, and reduces us players to mere button clickers...
Do you have any other "tricks" you know about, but a casual player might miss? Do you have solutions to eliminate them? I know there are plenty! Do contribute!
*) BtS.
Now I'm discussing tips and techniques that brings you from winning single-player games comfortably on Noble to being able to win at Monarch or Emperor; not pure newb stuff.
Some of you may even like things how they are. Please don't turn this thread into "don't change anything". Instead imagine that all the changes I'm discussing can be turned off with a switch.
My main point is that Civ forces you, the player, to keep track of things the computer rightfully should do itself. The realization that you can't escape the micromanagement if you want to improve your play beyond Noble (circa) is a definite turn-off for me.
PRE-CHOPPING
Do your Settlers take tens of turns to complete while your city doesn't grow?
Then you don't pre-chop your forests, and only then switch to a Settler build. In just one or a few turns later your Workers can complete several chops, thus producing the Settler, and allowing the city to get back to growing.
This isn't intuitive in that it goes counter to what the game says "building settlers halt growth".
It requires careful micromanagement (you wouldn't want your Worker to accidentally finish a chop before you're ready to switch to the Settler build).
The automatic settlers don't do it, which hints at an exploit.
But it is definitely useful, and so you'll feel forced to use it to compete.
Solution 1: If a Worker chops a forest in 5 turns for 50 hammers, then instead it should yield 10 hammers each turn.
This levels the field between casual players (and AIs I suspect) and obsessive perfectionists (i.e. good Civ players).
Solution 2: If Firaxis doesn't like the rather significant change this brings (in that you can no longer avoid no-growth turns unless you have loads of Workers) then the auto-workers should know about prechopping and use it.
WORKER-STEALING
I've got the impression good Civ players build very few Workers. Instead, they steal them from AIs.
I can't imagine this is "working as intended", and so:
Solution: Make AI Workers always consider enemy units to be hostile, except when you simply cannot declare war, and perhaps when the AI has decided to sneak attack the enemy civ anyway (and thus "wants" war). If the AI decides the Worker can't or won't move away, it should escort its workers!
The AI should especially take into consideration special abilities - such as a Woodsman II promoted Warrior, that can move two steps.
QUEUCHA RUSH
This isn't just about the Queucha unit, but in general.
Solution: The AI simply must take into account special vulnerabilities when deciding whether it's city defense is strong enough. For instance, it's exploitatively easy to attack Archers with Quechuas and Axemen with Chariots*. The AI should whip a single Warrior and Archer respectively in these cases, at least making the rush tactic harder than stealing candy from babes.
THE NO-DEFENSE CITY DEFENSE
Civ armies are generally stronger on attack than defense, despite the bonuses given for fortification, city walls, etc.
This is especially true for city combat.
So when faced with a huge stack (that has various units and no obvious weakness; and contains plenty of siege units too) what do you do: reinforce the city, massing your defenders?
No! What you do is retreat one step outside the city. The AI will fall for the trap and take the city, moving in his entire stack.
Now your siege units are right next to a city with no fortified units and zero defense!
This means you can attack, and your catapults (or artillery) will reduce his entire stack to minimal strength. Then it's a simple matter of mopping up, giving massive xp and probably a Great General too.
This way a stack can hold a front indefinitely even when facing several stacks that are each larger than your own.
This also means that once you've reached a certain minimum number of attack units, it makes sense to only build siege units thereafter.
This exploits the AI, and generally makes war into something strange with no basis in real life.
Solution 1: Redesign combat so newly taken cities aren't the death trap they are now.
BEING BEAT TO WONDERS
Yes, you can start building a wonder without any intention whatsoever to finish it. You're after the cash you get when an AI builds it instead. This allows you to run at 100% science for quite a while.
I suspect you simply get too much cash compared to the effort. Which may be less than perhaps the designers though, considering the 50% discount you get when you have the specified resource.
The original idea, to get a consolation gift when you're beat to an important Wonder, was perhaps a little too naive...?
Solution: I see no other solution than to reduce the amount of consolation cash. You should certainly not be able to get more cash than if the city produced 100% wealth for all those wonder-building turns (irrespective of Industrious and resource access).
UNIT QUEUES AND CIVIC CHANGES
Don't get me wrong, being able to order a city to build more than one thing at a time, as well as ordering "infinite builds" is nice, and definitely something to keep.
But good Civ players know better than using this queue only for convenience. Somewhat like pre-chopping, you can build a military unit to one round short of completion, then a second one, then a third one. This enables you to switch to warlike civics (Vasselage, Theocracy) just for a few turns while all those units pour out of the gates, getting those juicy xp, without having to endure those same civics for all the time it really takes to build those units.
After all, civics good for the military aren't the best for commerce and research.
And thus we have yet another way of getting to have the cake and eat it too...
Solution: Again, absolutes need to be removed from the game. You can't get the xp bonus at the end of production, the game must calculate what each turn of production yields (a fraction of a single xp) and then assign that, turn for turn.
Again, the reason for this change is to make micromanagement not worthwhile. Or, in other terms, make it so a good Civ player doesn't feel forced to use "techniques" like in this post just to be able to compete, as they make a game drag out while you're obsessing with details.
GENERAL MICROMANAGEMENT
As it is, micromanagement pays for itself. That is, you must do it, or resign yourself to playing at lower levels of difficulty. The only way to reduce this in the next version of Civ is by making it not worthwhile.
First and foremost, the game must be made aware of things like CE (Cottage Economy) and SE (Specialist Economy).
You must be able to tell your Workers "this city is running a CE, so DON'T BUILD ANY STUPID FARMS".
You must be able to tell your Workers "this city is running a SE, so BUILD ONLY FARMS".
FRACTIONAL RESEARCH
Apparently the way Civ uses whole integer arithmetic you stand to lose quite a lot of research of you set your science rate to less than 100% (once you have Libraries, Observatories etc online).
A true Civ expert would instead keep switching between 0% science and 100% science: full throttle until you run out of money, and then 0% to fill your coffers instead. This cumbersome way of doing it avoids losing fractional amounts, which saves you a lot of turns on research over the course of a long game.
And that's not even considering fringe benefits of stopping research for a while, such as getting bonuses for not being the tech leader in certain circumstances.
(And yes, I'm ignoring the Specialist Economy for the moment)
Solution: None other than using fractions in calculations. Of course setting your research to 70% for ten turns should give identical results to running at 0% for three turns and then going to 100%! Anything else is absurd, and reduces us players to mere button clickers...
Do you have any other "tricks" you know about, but a casual player might miss? Do you have solutions to eliminate them? I know there are plenty! Do contribute!

*) BtS.