Sounds like everyone have you great advice!
I had a humidity issue when I built my 1st set up. I cut a piece of cardboard to match the size of the screen top leaving about a 1 inch gap around the edges. I then cut two circles on both ends. I used a day time light to make the cage look like a display price and the other side I had a CHE to help with ambient temps. I gave about a half inch of extra space around each lamp shade. I then wrapped the cardboard with the aluminum foil. I live in mid-west and our average humidity is somewhere in the low 20's, even lower when the temps drop below freezing outdide.
I picked up some moss from petco/pet smart that comes in a green box... i would soak the moss in warm water, squeeze out all excess water then put some inside each of his hides. Every few days I would remove the used moss and re soak it in really hot water then ring it out let it cool for a few minutes and put it back in the hides. I would replace the moss all together with a new box monthly or sooner as needed. A larger water bowl helps a lot! Depending on how small yours is you could see close to a 10% gain with just that.
When I would see the first sign of an up coming shed (gray/blue eyes and skin color becoming dull I mist a few extra times a day. You might have to play around with how things are set up but once you get a shed that comes off all in one piece then you've found the sweet spot and continue with it. Soaking him in warm water with or without a mild soap during each she'd cycle shouldn't hurt. If I did a soak I would do it after their skin becomes less cloudy and dull, almost looking normal again. I found with my experience that it worked the best for my snakes.
Please be careful assisting your snake with dry patches of skin as you could hurt him by pulling them off. I've heard of people using a small amount of vegetable oily right before they shed. I would look into using the vegetable oil before you use it... ive never used that method. Hope this helps!<
BTW you have a beautiful bm?*