We currently just use a sheet and comforter. We have a king size bed so the comforter is pretty large, and since Rocky sleeps with us, I kind of like to wash it fairly often - downside, I have to go to the laundromat as it won't fit in my washer.
The only change is that sometimes I like to have a blanket as well, but the weight of everything just kills Shawn as he gets soooo hot so quickly. I like the weight personally. Plus we've always got the ceiling fan going and the box fan on my dresser - even in the winter (all for me of course).