You've asked me a multi-part question, which means that I'll really screw it up!!! Lots of guys use leaf litter (leaves) and it works pretty well. Mixed with a bit of fine soil, it holds moisture well, and your guy can burrow into it while he's watching TV or drinking tea.LOL
My setup may be a bit different. I've set up a humidity gradient (as well as thermal). I've got a humid bit (leaves) on the left, and a drier side (alfalfa pellets) on the right. The two are separated by a group of sandstone slabs (the nail file!)in the center. The warm area stretches across the rear of the enclosure. The cooler area stretches across the front. That gives 'em every temp/humidity variation possible. (the idea is like a "punett square", with three variables in one side, and two variables on the other)
65-70deg may be a tiny bit cool. I think the "best case" temp is supposed to be 70-72. I guess you could use a really low power ceramic heat emitter for a few extra degrees of "local" heat if you want to(they're cheap, and don't burn out).
DO turn the light out at night. I understand that it's supposed to be very important for their "circadian rhythm" and therefore their well-being.
PS If you opt for leaf litter, it helps to fluff it frequently (keeps it fresh, keeps it from rotting).
PPS I only feed on the alfalfa, or the sandstone (better for impaction risk, plus it's much easier to keep clean).
PPPS The sandstone can be easily stolen from construction sites. (Just kidding - if you ask the builders, they'll give you the leftovers)
PPPPS I'd love to see some pics of your baby. Post some when you get the chance. Post age/sex info (if you have that info). BTW, my guys discovered raw shrimp last night...it was frightening!!! I guess that'll have to be part of their diet now. I'm trying to figure out whether they'll eat cash. If I can feed them a steady diet of $10 and $20 bills, it would save me from all the runnin' around...
