So I've been playing GalCiv3 (after much procrastination). On a huge map (two down from the max), the game was slow, choppy, and prone to freezing. I started changing graphic options to try to increase performance. Nothing helped until I disabled LEAN maps. BAM. The game is now quick and responsive. The difference is amazing.

I'm thinking LEAN maps should be disabled by default, at least on lower end systems, for the sake of not putting potential players off the game. However, I don't know much about them. Are LEAN maps a standard feature of modern games? How noticeable is the benefit they provide versus the performance cost?

^ Just my non-expert thoughts on the matter.