Hmm, I was thinking more of near the end of the mission at the area with the platforms and lift station like where the beacon is located. I'll try to get you some images when I get home.
EDIT:
Alright, so we're going to have two variations here for this map:
- Red, stormy (but not rainy) skies: N7 versus Geth
- Clear, beautiful weather: N7 versus Collectors
Eden Prime is a naturally beautiful utopia-like planet. The reason for its redness and stormy atmosphere in Mass Effect 1 is because a colony on the planet was attacked by the geth.
Here's a concept art of the weather variation for the N7 versus the Collectors.
And here's the area in which I want the map's battle to take place:
http://www.youtube.com/watch?feature=player_detailpage&v=wyTtksDpTVg#t=379s