I agree. The quilting gives them a little spit and polish. I'm just making them up as I go along. If they come out too big, I can just trim them down. If they come out too small, I add a border. Piping, or no piping? I decide as I go along. I've been using scraps that are just big enough to do a back, usually in a contrasting color to the front. It's fun to be so free to create!
I have to say that I prefer to not use zippers. I used them when I first started, but I find that zippers can be scratchy sometimes. Now I'm making them with an envelope back. theire soft and one can cuddle with them.