I remember wayyy back in Civ II, you could send a convoy of food to promote the growth of a super city and establish a +1/-1 food relationship between two cities permanently. Wish there was still something like this.
Agreed, though using caravans to rush a wonder was just a tad cheesy. Not entirely unrealistic though, I suppose.
The really big deserts like the Sahara and Gobi still are mostly wastelands, even to this day. It's not unrealistic IMO. Plus it realistically models the fact that a large country will have huge, sparsely populated expanses.
They can still be sparsely populated, but they should at least be able to eke out a mere bale of food or a single hammer of production.
Even Libya irrigates its desert land. It has to get food from somewhere and unlike Egypt, it doesn't have the Nile with productive flood plains.
3) I'm not sure that this is really so unrealistic. Each tile in the game is something like 10,000 square KM. That's a huge area, and once an area that large has been cleared, assuming there is still human activity there, it's not going to grow back.
It is possible to reforest large tracts -
Germany has done so with its bogs and unproductive farmland for example. Maybe it should take specialised workers (engineers) and several years. It's not a quick task in Civ3 either, but it is possible.
You can irrigate accross a desert tile adjacent to a city that in next to a fresh water source, such as an oasis.
Maybe you're thinking of flood plains? I haven't been able to irrigate any deserts, not even oases. Those produce 3 food anyway but still, you'd think you'd be able to irrigate an oasis at least. It's sitting on water after all.
The fact that 1 empire will go the religion tech route and discover more than 3 religions shouldn't be allowed, IMHO.
Probably not. I've exploited this myself and everyone loves me after I spread my religion all over them. You'd think they'd hate me. Also, how realistic is it that you should be able to see a foreign city's military strength just because it has a church of your religion? Guess the Civ4 folks didn't believe in separation of church and state

. That would've allowed just about every country of medieval Europe to know the exact military strength of every other country.
As usual the balance is provided by the realism. Planting forests "might" be too good if an average worker could to it. But if some super-expensive modern worker were needed that you had to devote lots of food/hammers to make, then it becomes a strategic choice. That modern "Civil Engineer" if you will (Civ2 called them "Engineers") should also be able to irrigate deserts (greening deserts is a specialized skill) or mine or create roads in mountains (needed the "Explosives" tech in Civ2).
Agreed - the Civ2 land management was more realistic.
Even on huge maps I have never had much problem and load times are generally 5-10 second affairs
You must have a supermachine or something. That's about what it is in Civ3, but in Civ4, I'm waiting at least half a minute for a game on a standard map in the 1700s or so. It's not a top-of-the-line model but it's not ancient either. Judging from the graphics etc. between the two games, I don't see why there should be such a discrepancy.
The other objection is that no other enviromental factor is implemented. There's no little ice age during the 17th century, no extra mild age during the bronce age, no extra dry age around 900 - 1100 AD and so on. Landrising in the north have in reality changed the appearance of Viking land considerably since the Viking era, some of what is today prime land for agriculture was underwater just a thousand years ago. Big rivers like the nile have over the years created land where there once was ocean. Vulcanic activity have made huge impact on land from time to time. I could go on citing examples but the point is that if the climate changes and the land changes of the past 6000 years isn't reflected in the game why should we implement it for global warming?
Right, there's isostatic rebound, so landmasses covered by glaciers that melt aren't always going to be inundated by water. (The ice formerly weighing the crust down lets the land rise when the ice melts.) Ice ages and ice melting can also (and obviously did) happen without any global warming caused by human activity. Maybe the game should've implemented Milankovitch cycles etc. but most climate cycles like that are so long they might not even impact an average game.
But that reminds me of another thing - what happened to volcanoes? On one hand they could be a pain in Civ3 but could be fun too when they wasted someone else's city

. And obviously there's some realism there (Pompeii etc.). They were one of the only tiles you couldn't work in Civ3, but at least you got a few hammers out of them (not sure if that makes a lot of sense unless there's a geothermal plant there or something, but I wasn't complaining about it

).
I think it's funny that the OP is whinging about global warming being "broken" in Civ4 when it was just as broken in Civ3. Global warming caused tundra forest -> tundra, and there it would stop.
Where exactly was I "whinging" about it being "broken"? I said I never noticed it in Civ4 (maybe I have it off by default) - I never said I wanted it. I probably shouldn't even have mentioned it, since it has very little to do with my point. In this case, my point was it makes no sense to disallow forest planting.
I'm also unsure what their issue is with load times. I run a computer with only just the right specs for Civ4 and still get 5-10 sec load times in the late game. The only times I spend ages waiting for the AI to have their turns is when they get all trigger happy with the nukes. Either the OP has too many things running in the background, or he's running something rather ancient in digital terms (my comp is over 6 years old!)
Mine is at least to specs according to
this. (I find it funny that a "minimum" spec machine listed there with 256kb of RAM would even run the game

.) Dual-core 1.7Ghz 3GB RAM Windows XP SP2 32-bit. I'm not sure how you get 5-10 second load times late in the game. I doubt switching to a 64-bit machine would cut the times to a fraction of what they are now. I'm playing Warlords because I thought the spy system in BtS was stupid (got sick of getting sabotaged by puny civs every other turn) but there isn't a noticeable difference between vanilla Civ4, BtS or Warlords load times.