I always thought about looking through an iorn sight instead of the scope look or "over the shoulder" look. And a CoD4 like rank system with your character having perks like extra speed, being able to equip an energy shield only for your front, or extra health, somewhat like in SWB:RS. (What sniper wouldn't want a jet pack, or a stealth thingy?)
I do agree with the fact that bigger maps with more AIs on at one time would be nice, but the amount of AIs and size of map depends on the system, or computer power.
On my wishlist I want to see SWB3 on the DS with wi-fi, after all the DS is the 2nd best selling video game system so far, with the GBA in first. (The DS version would be so watered down it probably would have only 5 maps+ online play, and like a 7 mission story.) Despite how horrible it may sound, SWB3 for the DS would probably pass up CoD4 DS and Metroid Hunters, becasue of the FPS wi-fi. (The DS's wi-fi can hold up to 16 people at once, which convently is the same amount of people on the battlefield at one time in SWB2, but not SWB1 because on Hoth you can have 25 people, ya I counted them).
In the end I doubt extremly, that a DS version of SWB3 will come out. But it would be nice for someone like me who can't afford a next gen system.