With wet aspen you are risking mold in your tank. I would switch out the substrate to cocofiber, peat moss, or mulch. That substrate is fine for misting, not aspen. This is how I balance the humidity: soil substrate for glass tanks, aspen or papertowels for tubs (Tubs automatically have a high constant level of humidity). Overall, you want a dry cage over a wet one.
I personally am not a fan of large open glass tanks plus lights (day and night) for baby snakes because of the risk of feeding strikes from stress. Please read the ball python stickies when you get the chance. Have your snake eaten for you yet?