What's the best flooring?

For a plastic cage. Preferably something smooth and large so I can cut it to size. I have a medium size ProFleece Ultra Ribbed bed but my rabbit doesn't use it. Only ever hops over it to get to the litter tray. Sawdust makes cleaning a pain. I normally vacuum the cage easily because it's plastic, and quickly vacuum or wash the 5cm deep cotton bed. I have several chewed up thin fleece blankets which my vacuum cleaner doesn't manage to pick up the fur. I've noticed only when I layer the fleece blanket twice does my rabbit run around inside the cage, enjoying the bounciness.

Should I stick with carpet? She's okay laying on the carpet floor but I'm wanting something smoother.

we use vet bed for pens easy to wash, dry , cut to size