With that being said, do you mist or just provide those elements as you listed, I also believe that most of the higher humid terrestrials would be fine with just dry substrate, water dish always filled and a hide and ofcourse the substrate having good height to minimize chances of falls. If i had an arboreal i would hold the priority on humidity much more especially for avicsAs spiderling's they will burrow, I have 3 parahybana's 2 large ones and a small sling, they are very easy to keep, dry substrate and a hide and a water dish as adults...they are great eaters and don't hide or burrow as adults...great spiders IMO...
Regards, Mike