Our queen sized bed is my best spot for layout, which makes king sized tops a bit of a challenge. I have large rolls of heavy brown kraft paper I put down over the bed to protect it.
I typically spray baste, still intend to try glue when people stop giving me half-filled bottles of spray baste. For pinning, you might want to slide your cutting mat under the top, but I find a couple layers of the craft paper to offer a nice surface. I roll back up the paper and store it on the roll, and replace it maybe once a year or so when it gets flimsy, ripped, or too much spray residue.
In my highly desired strange quilting items, I'd really like (a) more space! and (b) one of those folding ping pong tables. They are a grand size and a nice height and fold in half when you don't want them such as in a garage, you just back out the car and pull out the table and instant large layout.