Stuck on next set up and what to do. (tank/AP/??)

Currently have a 20g long tank but I think it may be time to switch to something bigger. I was interested in getting a AP T8 since it seems like the best option but I have no idea on how to order the proper set up. The store by my house is having a sale on 40g long tanks for 50% off and I was thinking about getting that since all I know is tanks for a set up but if I can gain some knowledge about other options I'd prefer something different. The tank also looks HUGE compared to him and I think he would definitely stress out. I was stressing just looking at the thing! I want my BP to feel comfortable and I know that glass isn't the best for that, and covering every side is kind of silly when I can get something designed for a ball pythons needs.

I know a lot of people on here are very knowledgeable and was wondering then since I don't know exactly what to look for if someone could help me. My apartment is very cold but I have an gas furnace for heat so when it does kick on it gets extremely warm to the point I cant even be in the same room its located it. My temps right now in his tank range from 79-86 on the cool side and then 81-89 on the hot side. I have an UTH that I set to 89 and ranges from 86-91 temp on the glass. My humidity seems to be good and typically between 50-60%. My apartment is by the lake half under ground so the humidity is pretty high. To maintain these temps I use a 60 watt infrared bulb in the middle and then cover up on either side of the lamp. I also live in WI so its just going to get colder so my main concern is the heat.

Any help is greatly appreciated.