For me the GalCiv2 limitation was no mulitiplayer PBEM - easy to play and have time to plan. Nowadays the power of game is a real community to play together or develop the game together with mods. No multiplayer no strong community.
Even though I agree it was a weakness, this is not a deal breaker or limitation. There was a way to force it to hot-seat multiplayer, if wanted the problem is with even two players you need the time for each player to go. Multiplayer is obviously being addressed in Galactic Civilizations III so it's a mute point. The main focus of Galactic Civilizations II was making it a great single player game with no multiplayer so stating that it was a limitation is like saying that the Sims is a limited game because you can't play your sims in a city, the games were never designed that way so it is an intentional design.
You don't need multiplayer to have strong community, you just need a strong fan base, multiplayer does not make a game great, a good game that keeps the user entertained and into the game. Which I believe is the true nature of a game. Now as far as the other posts about the memory leak, well, I do notice that using a faster computer does limit this down some but does not eliminate, it's just too bad that this game reached "end of life" prior to somethings being dealt with. Ether way it's a great game and I look forward to the next version soon 
