Whats wrong with aspen bedding? I think it is the easiest substrate ever. I can buy a $4 pack of it and it lasts a month and a half (with two snakes though).
If you are using tubs, I would imagine you wouldn't relly need to mist anyway.
At the local petsmarts around jacksonville, the rodent section carries huge bags of compressed aspen for about 12 bucks or so its the same stuff they carry in the reptile section except cheaper, go figure. I buy a bag every couple months or so for my asf's!