all units should should have a pop. cost
That would slow growth down way way too much.
there should be city sprawl in that for every three or so pop. points there would be a new square of city(which would either go to the best adjecent square or the one of your choice)
How big is a square supposed to actually represent, though ?
I like the thought of cities spreading, and being able to work larger areas when they spread, but I've never seen a mechanic proposed for that that actually sounded workable; I'd be inclined to think that maybe size 20 or 40 is reasonable for this.
public opinon should play a much greater role. each citizen on top of the normal happy/content/unhappy indicator should also be things like conservative/progressive and pacifist/agressive. expansionist/isolationist
I don't like that as a notion; it would be frustrating if it were outside your control, and I don't really see any way in which it would be fun or useful if you needed to control it at a more detailed level than "citizens you keep happy are more likely to do what you like."
civ triats should change over time based on gameplay style. no one would today would say that britian is expansionist.
Individual civ traits should be scrapped; the differences between civilisations should be entirely at the strategy/gameplay level, and if you really want the specific bonuses that specific traits have, put in a wonder that gives that benefit so players who want that benefit can make it a priority of their strategy to get that wonder.
religion should not be rigid. you should be able create your own religion in a more complex version of the civics screen. worship/salvation/deity(deities), etc.
What would be the point, in gameplay terms ?
there should be scales on the civics screen on top of a more complex system such as a libertarian/totalitarian civil liberties, communist/capitalist/command economy, etc. as well as a constitution option which would affect happiness and war weariness as well as the stability of your goverment.
Civics should be scrapped, and fixed governments reinstalled; I'm all for a wider variety of fixed government options, though.
empires should collaspe upon ideological,religious,cultural differences and geological isolation.
I see no reason to simulate this at a level more detailed than cities going into anarchy when too many people are unhappy, and governments collapsing when too many people go into anarchy; what would it add to gameplay to have a different mechanism in there ?
costumizable units are a most and experience should be able to be bulit in with a production cost. e.i. training
I am very strongly opposed to this. Fixed units, same units available to everyone, no training or experience beyond promotions to veteran or elite as in Civ 3; if you want a unit that's stronger in a specific direction, make it a different unit, not a promotion.
civ should start far earlier in mans past and end far longer in to mans future. start with fire and the concept of time, death and end with terraforming and solar wind propulsion etc.
I'd say a little farther into the past, and optionally a way into the future.
if you have it to were the populize elects you you should have to worry about getting elected agian.
Again, what does it benefit the gameplay to have this work at any level more complicated than anarchy as I describe it above ?
there should be 4 turns per year. it would make it much more realistic.
Realism is only worth having if it makes the game more fun, and I don't see how this idea even adds to the realism.