I'm not sure what you mean when you say you're "his heat source a lot." What size enclosure are you working with? My room stays right around 74 and a 100watt CHE in my 40 breeder (heavily modified mind you with duct tape and foil, as well as insulated on three sides) keeps my temperatures both warm and cool where I want them.
I don't mean to come off as abrasive, but it seems like a lot of your issues are coming from having minimal equipment. Have you considered doing some alterations to your enclosure to make the most out of what you have? Below is a really good post about setting up a glass enclosure that will retain heat much better than a barebones set up.
https://ball-pythons.net/forums/show...With-Pictures!