I think chloroplast is fine actually, in that it provides a hearty structure and flat floor. I would not use it on its own though. In all the C&C cages I’ve built, I have used cage grids for the floor, with chloroplast zip-tied to it for an even flooring, and then carpet on top of the chloroplast. I use the low-ply carpet squares you get at the home improvement stores for easily installation. One of my rabbits recently became at risk for sore hocks from a utility rug I tried for a bit, so to give better cushioning, it is now .5in memory foam with a fleece fabric tight on top for the flooring (on top of chloroplast).
This is what the flooring looks like, which is chloroplast below, foam on top, then a grey fleece covering it: https://www.instagram.com/p/CJjfWYPFF3w/
This isn’t in a cage, but it’s leftovers that I used to floor one of their hidey holes.
Here is an example of when I used to use the carpet squares:
https://www.instagram.com/p/B6LmVsUAfdv/
The answers provided in this discussion are for general guideline purposes only. The information is not intended to diagnose or treat your pet. Seek the advice of your veterinarian or a qualified behaviorist.