A game not designed for multithreading will never be. It need to be re-written from scratch. Next generation engine based on Direct3d 11 engine (who is multithreaded) will bring a lot more multicore optimisation. But dont ask for SoaSS to become multithreaded by magic, it will not happen. but if you use a mod with a bigger map and the game slow down, it can be 2 things in my opinion 1. AI algory
Punkenjoy
First, Ironclad designer had budget for model, texture and other thing so in the end, the game were running smootly. Mod dev should try to stay within theses budgets. Every game engine will look unoptimized if you overide the budget. Take the latest unreal engine, put full of 10 millions polygons models and you will kill the performance so bad that it could crash at launch ! Anyway, for the x64 vs 32bit, if we take a look to the steam survey
i haven't read all post but i want to tell to the dev that: I think you do a realy great jobs. Some bug at the release for me (savegame 0k and creating a custom ship bug) but i can live with that. Normaly i don't buy a game at the release because they have normaly too much bug! (and even more if it's a EA games products ...) But for Galciv2, it seem to have very few bugs for a so complex game. i buy the game online and download it