Mine have a low nap indoor/outdoor carpet in the bottom of their cage and their shelves have a very tiny wire mesh on them (doesn't hurt their paws as the mesh is tightly woven (I can't even put the tip of my pinky finger through it, it is so small, so no worries about their paws).
Our experience has been one of trial and error. Our first rabbit, Rascal, was destructive and managed to chew through everything we tried. She couldn't chew through the wire though so it was perfect, I resorted to replacing the carpeting every couple of months as she did chew through it, but had also chewed up linoleum, plywood, blankets, towels, etc.
Rascal was recently re-homed along with her boyfriend, Bitsy (father of her babies). We are left with 3 buns from two different litter, teenage girls (10 months) from Rascal's second litter (first litter was stillborn and how we discovered that our boy rabbit was actually a girl) and one little boy from Rascal's third litter (he's about 10 weeks). None of the three have their mother's tendencies to chew on everything in sight so we are making changes to their space. I am not sure yet what I will do in the end, but I am thinking of changing out the wire mesh for something softer. We used to use grass mats but Rascal chewed through those in a few hours and Bitsy a few days so they weren't worth the cost.
For litter, right now, we use pine shavings. I had no idea we shouldn't be using pine until yesterday when I read it on here. We are on a mission to find wood pellets now. I am excited about making the change because the pine shavings are a fiasco. Seems like half our house is covered in bits of pine and boy is it annoying. My 10 year old is in charge of changing the litter and she manages to string it from one end of the house to the other. LOL