Fantastic posts Psyringe!
I'm not that 'extreme', but I play much the same way you do. Prefer big maps with many civilizations and I love the economic, scientific and diplomatic parts of the game. Usually fight some wars too, but it depends on context and I always try to keep them short. Rarely have big armies, so long wars wouldn't be great for my playstyle anyway.
You explain very well why Civ 5 put me off too. They removed too many features I liked. Feels like there is no information any more, and the UI was just horrible. The whole game basically became about money too, which I didn't like. 4 handles that part much better too.
I'll concede the 1UP changed the combat tactics a bit, for the better, but like Psyringe I don't like to wage wars so it's not really a good change for me. The AI was also so utterly ret*rded that it didn't really change much. With big armies it also became a nightmare to manage the things, with just about the whole map covered with units. Try moving stuff around then. Not cool.
Unfortunately my computer couldn't quite handle the big Earth-like maps that I preferred playing, because my games are looooong so it became very slow at the end. Waiting 30s+ for the AI to make its move gets boring quickly. But I loved Civ4 because of its depth and all the options it gave me as a player. It was fun just browsing around the cities and checking out information about how they were all doing. Some of the mods were great for that, the UI mod in particular.
Civ5 need the modding community to sink its teeth into it, but I'm not sure they can do what is required to make it nearly as good a game as Civ4 is. The UI and underlying gameplay have changed too much I think to be fixable by the community.
So frustrating when great games get 'ruined' in follow-ups because of a new writing/development team with different ideas, who throw out everything that is good and focus on other aspects instead - usually combat. It's probably the prime reason why I dislike ME2 and (soon) ME3 too. But I'll enjoy the old-ish classics instead :)