I always use Repti-carpet, and put substrate on top, like you, however I use aspen. I actually have two repti-carpets, when I clean I grab the edges and pull most of the substrate up all at once, and then replace the Repti-carpet with a clean one, and then I clean the dirty one. Its a pretty useful system, and never had any problems with it. Your set up looks fine!

Also consider the cheesy background/foamboard idea stolen! I will most likely be using it in the near future.