My main concern with mosaic style tiles would be cleaning all the grout. Bunnies can be messy at times and getting the cage truly clean in all those grooves could be a real pain. I would avoid the porous tile completely.
I used linoleum flooring. It was a single piece cut off a roll and then I cut it to size at home. I used a spray adhesive which made things easy. I like the whole piece because it means that there’s no connecting grooves for liquid to leak through and no hard cracks to clean. While it can be slippery, when moving slowly my buns manage alright, however if they get a fright, the linoleum is too slippery for traction at speeds. I use fleece over the top of the lino. I clip it down with bulldog/fold back clips which makes it easy to remove and change for cleaning. Tile would certainly be cooler which is a concern if your house gets quite cold, and you would need to layer up with blankets to stop the cold seeping through from them in winter. My buns aren’t a fan of hard surfaces so I can’t imagine that they would like tile much, however my previous bun, Bandit preferred to lay on the bare linoleum than on fleece.