Personally, I find that cats like to be a little underpotted. My cinnamon tabby cat used to curl up in an 8x10" box that use to hold photographic paper. He was so big and fluffy that he overflowed the top of the box, looking much like a large cinnamon cupcake. What a hoot.
Lots of good, happy years to you and your kitty. Thanks for the photo!