What about rail fence for a pattern? It always looks more complicated than it actually is.
Can you talk them into doing a raffle instead of a silent auction for the quilts? You can usually make a lot more money on a quilt in a raffle than you can in a silent auction.
Oh, another idea is a D9P set on point. Saw one on the board here that looks really nice. Will post a link to it if I can find it.
OK, here's the link, but I had forgotten that it is a scrappy quilt:
http://www.quiltingboard.com/t-99696-1.htm