If he is just climbing at nightime I'd say he just enjoys being out and about at night. Maybe looking for food or something??
Your temps seem OK as long as your are measuring the ground temps, which I'm assuming you are.

I have my BP in two kitty litter boxes and there is tons of room inside.
She doesn't seem to be upset about the extra space but I'm not going to argue about the size of the hides.
I do agree they should be tight!

I think your BP just likes to roam around. As long as he is eating, sleeping, and pooping, and sheding OK I'd say you should be fine I think...