So.. I suppose this is an old-timer rant... bear with me 
Civilization I was my first ever PC game. I had just migrated away from the Amiga 500 to an 486/50MHz, and the year was sometimes early 1990s. I still remember playing (and losing) my first ever Civilization game as the Egyptians... Comrade Stalin was just simply far too war-crazed a neihhbour. I played the game through the night, which was to become an all-too common phenomenon. Anyway, I got hooked to Civilization like pretty much every other strategy gamer of the past couple of decades.
Civilization II has probably cumulatively destroyed more of my time than any other game so far, and Civ3 actually made me waste about three days, excluding one math lecture and a few hours of sleep, in creating my best overall result of my Civilization career. So... I'm pretty much a veteran.
But... then came Civ4. It's visually pretty and all, but I am still ambivalent about the game itself despite having tried to play it quite a lot. Some of it is probably because of me not being able to adapt my play style, and I'm willing to admit that. That's probably why I'm posting; I really want to know what I am missing here
There are various things I'm not comfortable with in Civ4. It seems to me that Civ has fallen into the "Call to Power" trap of introducing too many pointless new things that don't materially contribute to gameplay. The units' promotion system and the introduction of (politically-correctly neutered) religions are the worst offenders; I still can't see why they are there. They just seem to add unneccessary complications to the game, and the religion bit is even more superfluous than the unit promotion bit.
The Civics system is questionable as well. I much more preferred having distinctive, consistent governments to choose from, that had reasonable effects on my civilization. A lot of the Civ4 civic options seem to be arbitrarily assigned to their categories, and it just seems to give me the feeling that I'm just supposed to race through all of them so that I can get to the top-level free-market democracy. In Civ3, your choice of government at least made practical sense, and there was a time when you wanted to be a warmongering Fascist.
Civ4 also has aggravated the problem Civilization has had from the start -- the early game just whooshes by. Nothing happens before 1000AD, and the new tech tree makes things worse. Tech trading has been intentionally nerfed, and the tech tree itself has become stranger... you get Alphabet really late in typical games. You Alphabet and Literature around the the time you're building the Sistine Chapel! This is historically totally, totally weird. The ability to write arose earlier than Civ4 makes it seem like, and you don't need writing to exchange Archery for Animal Husbandry. The Civ4 tech tree system also means that you start getting meaningful communications with other civs far later than in earlier Civ games.
This ties into general pacing issues in the game. Civ4 gives me the impression that the game advances way faster than it used to, and that I am strangely always behind the curve no matter what I do. I have trouble understanding where the human player's edge is supposed to be here. Now, I am all for good AI in games and I hope this is what I am seeing here, but I get the distinct impression the computer players are in cahoots ... or that I'm just missing something. I hope it's the latter.
So.. I'm all ears... what should a Civilization veteran do to improve one's game in Civ4, so that he would not always find that he has just been clicking "next turn" until 1000AD where he is hopelessly behind?

Civilization I was my first ever PC game. I had just migrated away from the Amiga 500 to an 486/50MHz, and the year was sometimes early 1990s. I still remember playing (and losing) my first ever Civilization game as the Egyptians... Comrade Stalin was just simply far too war-crazed a neihhbour. I played the game through the night, which was to become an all-too common phenomenon. Anyway, I got hooked to Civilization like pretty much every other strategy gamer of the past couple of decades.
Civilization II has probably cumulatively destroyed more of my time than any other game so far, and Civ3 actually made me waste about three days, excluding one math lecture and a few hours of sleep, in creating my best overall result of my Civilization career. So... I'm pretty much a veteran.
But... then came Civ4. It's visually pretty and all, but I am still ambivalent about the game itself despite having tried to play it quite a lot. Some of it is probably because of me not being able to adapt my play style, and I'm willing to admit that. That's probably why I'm posting; I really want to know what I am missing here

There are various things I'm not comfortable with in Civ4. It seems to me that Civ has fallen into the "Call to Power" trap of introducing too many pointless new things that don't materially contribute to gameplay. The units' promotion system and the introduction of (politically-correctly neutered) religions are the worst offenders; I still can't see why they are there. They just seem to add unneccessary complications to the game, and the religion bit is even more superfluous than the unit promotion bit.
The Civics system is questionable as well. I much more preferred having distinctive, consistent governments to choose from, that had reasonable effects on my civilization. A lot of the Civ4 civic options seem to be arbitrarily assigned to their categories, and it just seems to give me the feeling that I'm just supposed to race through all of them so that I can get to the top-level free-market democracy. In Civ3, your choice of government at least made practical sense, and there was a time when you wanted to be a warmongering Fascist.
Civ4 also has aggravated the problem Civilization has had from the start -- the early game just whooshes by. Nothing happens before 1000AD, and the new tech tree makes things worse. Tech trading has been intentionally nerfed, and the tech tree itself has become stranger... you get Alphabet really late in typical games. You Alphabet and Literature around the the time you're building the Sistine Chapel! This is historically totally, totally weird. The ability to write arose earlier than Civ4 makes it seem like, and you don't need writing to exchange Archery for Animal Husbandry. The Civ4 tech tree system also means that you start getting meaningful communications with other civs far later than in earlier Civ games.
This ties into general pacing issues in the game. Civ4 gives me the impression that the game advances way faster than it used to, and that I am strangely always behind the curve no matter what I do. I have trouble understanding where the human player's edge is supposed to be here. Now, I am all for good AI in games and I hope this is what I am seeing here, but I get the distinct impression the computer players are in cahoots ... or that I'm just missing something. I hope it's the latter.
So.. I'm all ears... what should a Civilization veteran do to improve one's game in Civ4, so that he would not always find that he has just been clicking "next turn" until 1000AD where he is hopelessly behind?