CIV III has its quirks and faults but CIVILIZATION IV has to be one of the most awful versions of turn-based strategy ever developed. Where did they go wrong with CIV IV? Oh, let me count the ways. The globe-based map is one of the worst parts of the CIV IV experience. It's too small -- or feels too small. The unit icons are too big.
CIV V seems to retain that aspect of CIV IV, but I'm hoping it's toned down. The CIV III world structure was much better, although I probably won't mind switching to a hexadecimal map. The squares were limiting in some ways.
I rattled off an extensive list of features I wish CIVILIZATION would bring back in this SF-Fandom discussion of CIV V. I miss spy units from CIV II. I miss engineers (and their ability to transform any kind of landscape). I miss airbases. I miss partisans.
CIV V handles armies in a radically different fashion. You can no longer stack them up but have to place units in adjacent hex tiles. Units will be able to retreat and switch out but the battles probably won't be as "realistic" as in earlier versions of CIVILIZATION in that they will be stretched out over huge swathes of territory.
Now, technically, that is the way modern wars are fought, but most ancient wars were not fought that way. So I may need to just wait and see how the game plays but I always like having multiple stacks.
I wish for many things with CIVILIZATION, such as the ability to create naval bases. Why should I have to make a ship limp dozens of tiles across the map to a friendly city? Why can't workers/engineers be used to create naval bases and airbases along with fortresses?
Something else I wish is that fortresses stay the same when technologies upgrade. I'd rather have the ability to choose to upgrade a fortress than to just have it automagically transform.
And I've always wanted to claim territory with fortresses. They introduced colonies in CIV III that just vanish when a rival civilization's cultural influence spreads to the colony area. I'd rather see the colony stay with the civilization that built it. But that's just me.