Quilt.......
Should be at least queen sized
Design choice is yours completely, remember it's your time.
applique seems to be an attention getter.
What's in fashion now? Seriously, I don't follow fashion so I can't answer. I'd lean toward neutrals myself.
Try to keep it gender neutral. But your audience will mostly be female probably so don't sweat that.
And I agree, if you can, try a raffle. Usually more profitable.