Congrats on the new snake! Your temperatures sound fine to me, a cool side ambient of 78-80 is generally accepted for ball pythons. Plus most snakes are not going desiccate if their set ups are one degree off. For humidity, I'm not sure what you mean by false reading? Is your hygrometer touching the rags? If not it should just be measuring the air around the sensor. If you are still worried about humidity, it doesn't hurt to offer a humid hide as well, a lot of snakes like them. Also in the future it might be easier to maintain all these parameters if you invest in a PVC enclosure. I know you've already put all this effort into making the glass enclosure work, but it really is so much more of a pain, especially at that size tank.
One last thing, please try to format your posts so they are easier to read. The block of text can turn some people off, and information is more easily missed when it's presented like that.