Awsome looking cage wetone, I am in process of building a new cage with the exact design. I found plans for this design somewhere on line and modified it to suit my needs. Should have it complete in a few days will post once its complete. I like the way you installed the drip pans in the bottom! Still undecided about this option.
As far as Stain & Clear coat goes, this will not cause problems for Chams, I have seen many threads regarding this issue saying do not stain or clear coat your cage but have NEVER seen or heard of any issues to CHAMS by doing this. I and many of my friends have stained and sealed numerous cages using clear coat (oil & water based) with no ill effects.......
the key to this issue is to always let the clear coat completely dry and air out; preferably outside for at least a week or so. If you think treating wood

is unsafe for CHAMS then just dont do it.....nuff said