How about do your own 3d version of Castlevania? As in the castle itself?
Might be a lot to take on, but it could be cool to see.
I like this idea, at college making a simple castle was one of the very first assignments.
In addition to competition ideas I'd also be interested in knowing if there is anything that might be preventing other members from joining in so that we can try and brainstorm some ways to make the competitions as open to everyone as possible.For example it could be that you think the timeframe is too short, the subjects too hard, or you feel a bit out of your league with some of the higher poly models being submitted.