I,too, have occasionally looked at the contests - and then at the requirements. Actually, for me, getting the final item photographed and the image on to the QB has been one of my big stumbling blocks.
How about a few themes being color based?
Such as green dominant or purple dominant?
Are "holiday-themes" discouraged? (Such as Christmas, Fourth of July, Thanksgiving, etc?)
How about quilts made from old jeans/denim? I've seen some great ones on the QB - that were NOT rag quilts.
Or innovative rag quilts?
The size restriction - seems reasonable to me - somehow putting a potholder in competition with a bed-spread king-sized creation/quilt seems unreasonable to me.
As to the skill level issue- I consider myself an accurate advanced beginner - I look at some of the projects and totally ooh and ahh over them.
Maybe contests with limits as to the total number of pieces in the finished item (excluding backing and binding)?