I love using a sleeping bag. I just throw it in, then I get in the hammock. Push my feet and legs into the bag to stretch it out, then sit up and throw the rest of the bag behind me toward the head end. Done. There's something magical about zipping that big fluffy hood around your head - warm and air tight except my ice cold nose.
Plus, my Marmot bags allow you to move the down to the top or bottom giving you a truly versatile quilt when temps jump around on you.