Listen up...This post is making my head hurt. I'm making this as easy as I can for you...
Shoebox bin- 6qt usually works best 1$
Thermostat- Zilla 50/Ranco 100(Had zilla for over a year (still do) and have had 0 problems. Just make sure you monitor temps daily...
Thermometer- 1 accurite thermometer with probe
Cypress mulch- Big bag from home depot cost me 4 dollars
Ramiken dish- water dish that can be bought just about anywhere
UTH heat pad- zoo med ones work fine 10-20
Small coconut hide- 6 bucks
Thats it dude. Don't over complicate this. Poke a bunch of holes in the tub 4 on the long 2 on the short side. Pour some cypress in, fill the water dish, and add the hide. Adhere uth to bottom, plug into thermostat, and plug thermostat into wall. Take thermometer probe and hot glue it to the INSIDE of the tub over the UTH. By doing this you monitor the exact temps the snake is sitting on works great. Tape tstat probe to the outside of the UTH on the bottom of the tub. So one probe is on the inside, and the other is on the outside. Not rocket science. Chances are if you think what your doing is too complicated, then it probably is. You don't need three thermometers thats ridiculous! Humidity will be fine in the tub as long as you keep the cypress moist by misting a couple times a week if that. As long as your room stays at about 77-83 you should be fine. Only thing I monitor in my tubs are the hot spot. I know the temp in my room because there is a thermometer in my room, and I know that tubs keep humidity within 40-60% so I don't need a hygrometer telling me the humidity all the time. It might be a good idea at first, but if you KNOW how it works you really don't NEED it. The only other time you need to watch humidity is during shedding, but just mist the enclosure daily when this occurs and no problems will result. People like to get a little tech happy with there setups, and to me its just unnecessary.