A 82 hot side is pretty low, and you can pick up a Digital thermometer for 10$ at Wal-mart, with a light and a heat pad I don't know how its only 82 though. Normally people have to tone those to things down because they pump out too much heat, it must be freeeziingg in your house!. I would get the digital on the hot side to see what it says, as far as the size of the tank, I would say as long as your snake is eating I wouldn't worry about changing it "theres no point" thats the only thing the size of the tank would effect. Humidity isn't all that big of a deal, the only thing the snakes REALLY need it for is the shedding process, which you can see coming, and just bump up the humidity a bunch when they go into shed.