Well, looking at these proposals: http://springrts.com/wiki/Google_Summer_of_Code_2011
, I could probably do the AI interface part, as I've already sent a small patch and did some work on creating the new C# AI interface until I saw what great work ivand did with the RPC thing.
Also, even though you don't have that listed, I'd like to be able to have a way to add/remove teams, add/remove/change alliances (possible?), have shared or unshared vision (regardless of alliance status), add/remove AIs, have unexplored (completely black) parts of map, modify current vision, all through Lua. Also a few more functions that are currently possible through /commands would be great to be exposed in Lua (/globallos, /specfullview, /team), etc.
I'd like to have that for my in-game scenario editor anyhow, and I don't mind getting my hands dirty, but I've got little to show regarding engine work except the other work I did in regards to spring projects:
(has an early WIP of the scenario editor i'm making)
These projects are of course based on someone else's original work (springgird and botrunner) or I'm using them as a framework (Toolbox).
PS: The stuff I mentioned above of what could be done are just examples from my point of view (not knowing full well how much work it would require). It would be great if you could update the wiki page or add a couple of suggestions of your own. I'm sure there are some other people that would work but are lacking ideas or insight into how hard or useful something would be.