The T10 is what my BRB and one of my boas is in. It is tall enough (15" I think) to add a basking shelf if you want to give the BP climbing space. My boas use it all the time to stretch out.
Heating depends on ambient temps. I keep my reptiles in a dedicated room and heat the room to 75f, so I only need to provide hot spots for them. If your house stays cold, you might want to add an RHP. AP does not install them, but I believe they work with pro products and you can order one through PP and they will ship it to AP who will install it (you need to let AP know too).
For ordering frozen, I'd figure out how many feeders you use in a month and get enough for ~2 months (or more) of your current size and then a package of the next couple sizes up (or at least 1 size up).