You need to get that cool side up a bit higher, around the 80 - 82 degree mark as 75 is a bit low. If it's too cool your snake could become ill or will just refuse to use the cool side hide which ruins it's ability to thermoregulate. Glass enclosure's seem to be so much work! We have only the big boa in glass and it took ages to get it set right for him and it's still more of a worry than all 6 of the ball python's plastic enclosures.
We use pure aspen in the ball's plastic enclosures and a mix if aspen and cypress mulch in the boa's glass enclosure as the cypress does help a bit with the humidity in winter we've found when we mixed it in with the aspen. Watch cypress though, it tends to come wet in the bag and needs to be baked to dry it and also remove any issues with bugs in it (lot of work in my mind so we only use it during the winter months in the big glass tank).
~~Jo~~