Its looking really nice, I'm curious about what your paint recipe is for the white you use.
As for chipping, I always used to use the foam that came from the blister packs, but I am all out of that now, what do you use?
Also, you said you were thinking about adding to your bases. Something I found pretty nifty is watch gears. You can get a pack of like a hundred or so on ebay for pretty cheap. Just something I found if you were thinking of going that way.