I have a temperature gauge, and the fancy lamp, so do I really need a thermosat? And also, I'm just asking questions that my Corn Snake book doesen't cover, I used to have a snake named Troy, for about six mounths before he escaped, so I do have at least some experience with snakes, I also had a pet snapping turtle named Snapper, but I cought him in the wild, and so he wouldn't eat so I had to relese him to the pond I found him in. Also, I have read about herps and animals since I was eight, So I know some stuff about snakes: Examples, Herpetology, Science of Reptiles and Amphibians. Reptiles and Amphibians were originaly classifed togeter; in the same genera or family, not sure...
Answering the question bolded and in red first. YES. Buying a thermostat has been recommended to you several times that I've noticed. Yes, get a thermostat. A thermostat will keep the temperature of your heating device (have you also noticed the vast number of recommendations to use the Under Tank Heater?) where you want it. The thermometer lets you verify that the thermostat is doing its job and, if you have two of them or a dual zone thermometer (fairly cheap at walmart), lets you see what the cool side temperatures are too.
Ditch the fancy lamp. By that I mean "return it and get your money back and spend it on a thermostat. Corn snakes don't need UV.
Ditch the 'wet plants.' Just because it's been cold up there, even freezing, or below freezing, doesn't mean micro organisms didn't survive.
Not knowing where you are in New Hampshire, I just looked at Weather Underground for a sample of locations. Humidity is currently running from 36% in Berlin to 60% in Keene, with most locations reported in the 50% area. Yeah, that's a bit dry, but not too bad. You could try a quick spritz of mist once a day to help bump it up a bit. Maybe you have a small room humidifier in the basement. Drag it up, clean it off and use that to raise the whole room up a bit. Or just create a 'wet hide' by cutting a hole in an empty margarine dish and putting some damp paper towels in it when your snake is in a shed cycle. Come summertime, you probably won't need any artificial means to raise humidity.
I admire your enthusiasm, I really do. Honestly, I do! But stating your experience as you did above is like saying you have read a lot about airplanes and you once built a remote control model that you flew for a few months until you crashed it, and now claim to be able to be an authority on the F-16. Sorry, you're not. You're getting there, and maybe some day you'll be the best pilot in the air force.
Ask questions. Get answers. Gain experience. That's how you'll get good at it. Don't argue every time someone suggests you rethink something you're doing.
Did I mention that I thought getting a thermostat was a really good thing?