I still am waiting for an 4x game that can rival MOO2. Imo it`s economic system was even better than Civs one (at least lategame). I yesterday bought Gal Civ 2 to give a try again because I still remember not liking the system that much after I tried it a few years ago. After reading the article I maybe should have bought SotS instead (both were low prize) but than I would have missed on the diplomacy features...
IMHO the way you have to manage your planets in MOO2 is just superior to any other 4x space game I know. I really like the face that you just have to build buildings once to get bonuses as this reduces pesky micromanagement enormously (until lategame, when you started to have to update every single planet every now and then). You can have building queues for 100 and more turns and the important decicions regarding production/reseearch/food/income can be dealt with using 1 interface screen. Together with the transport system this allows for some deep strategies without even having to go into the single planet interface once.
I did like Ascendancy (tile management) for example but updating the different tiles as soon as you wanted to change a planets strategy or got a new improvement just became a chore. Civ4 does have a similar problem. Although you´re building a citys improvements only once, managing the surrounding tiles and units lategame just becomes too much micro. I loves this game but almost never finish a huge world as round just take too long at a specific point (1850 til 1900 when you are the dominating power but would need 100 years to conquer the plant; going completely war production would speed up the process but result in even more micro).
MOO2 endgame is more like starting to build ships everywhere (huge queues), setting up some automatic rally points and then just having to move huge armadas with 1 click. It basically had depth, the possibility to micromanage but without too much need of it.
Sadly MOO3 although probably having the most sophisticated economic system on paper (!) just did not do it right. They tried to implement everything and it almost sounded as a simulation instead of a strategy game. And then you could not figure why things happened because everything was calculated behind the scenes.
I still hope that some day there will be a 4x game that can rival MOO2s complexity and accessibility. But IMHO it is still the best of its genre even after 10+ years...