All, I think we could benefit by borrowing an idea from the NAQCC. The North American QRP CW Club runs a two hour Sprint each month that seems to bring a fair share of ops out of the woodwork. New members are always being added so they must be doing something right.
A digital mode Sprint should show similar results and putting the emphasis on multi-mode contacts for additional points would take care of the modes that sit dormant. There's also the camaraderie and the opportunity to sharpen skills on modes that are less familiar. Just a thought... See http://www.arm-tek.net/~yoel/index.html Tony -K2MO