I am not an expert, but I will tell you what works for me. I keep my snakes all at room temp, around 82-84 during the day and 72-75 at night. I use no heat pads, heat tape, etc...I have a baseboard heater that I keep on 24-7 that heats the whole room. Only during the day, I use an osculating fan (on low speed) that sits on a table close to the heat source that circulates the air around the room. That way the top and bottom of the rack stay at the same temp. I turn the fan off at night, since it is starting to cool off. My snakes have no problems, they eat, digest, and shed nicely.
This is only my 2 cents. I used to use all the heat tape and whatnot, but found that this way is what I like best.