From the photo it looks like the top is mostly glass with a little bit of screen? That's actually a really good setup. I wouldn't worry about the cold side temp myself, it's better to have it a bit too cold than to have it too hot, you don't want to cook your snake. I usually dial in the hot side to about 88F. My ambient temps are low to upper 70s, I think you are fine there. You could probably bump up the humidity a bit, I'd rather see it a bit too high than a bit too low. When my snake is sluggish and I crank up the humidity to nearly 100% they pop right out of it and look great. I usually crank it up high and then let it fall to 50% to 60% before cranking it up again.
Never heard of boiling a rodent LOL. I usually defrost my rodents in the fridge overnight, then put them in an incubator at 110F. I pull them out one at a time to feed, if I pull them all out at once they get too cold and the snakes won't eat them. The trick to feeding frozen thawed is to get the rodent temps perfect, should be about 100F to 110F, very difficult to dial that in. And should be raw, not cooked LOL. If you feed one that's too cold or one that's too hot they can freak out and go off of feed. If you feed one that's warm on the outside and frozen on the inside you can kill your snake. I usually like to feed fresh killed, you can make a CO2 chamber pretty easily using small canisters of CO2, like the ones you use for BB guns. Costs about a dollar shot to put down one or more mice. Also, if you thaw out a rodent I wouldn't refreeze, you risk it spoiling. How old is your snake? You should post photos. Be sure to watch for mites, they look like little black spots on your snake and sometimes can be seen crawling around.
Congrats on your first ball python! There's a ton of information on this site, just post whatever questions you have and people will jump in to help.