The hot side only needs to be up to the mid-80's not 90. 90 is where you will start getting burns. If the cool side temps are okay (70-75) without the light, I wouldn't be using it. Only because it wouldn't be giving me anything extra. If you need heat to get the cool side up you might try a red/black heat bulb so it can be used at night as well. UTH's can be unstuck if you carefully peel it off. There's no guarantee it will work, but I've removed mine from under one tank and read of lots of other people who also did so successfully. If you put it under the tile and put it in the tank you would probably have to monitor the temps again to see where they are at. I, personally have no experience with this method. My UTH is attached to a piece of picture frame glass and put underneath my tank. It is also connected to a do-it-yourself rheostat (
Rheostat Link ) that allows me to control the temps much more effectively.
More hides could make him come out more. It's tough to say, but they definitely couldn't hurt things. I think most people, myself included, have to get their snakes out of the hides when they want to handle. This isn't a bad thing.
Him seeming really mellow when you handle him is a great thing, imo. Some snakes go wild when held and squirm or bite. Some are naturally much more laid back.
Furry poop after moving up to fuzzies or other "furry" prey items is natural. You
can feed a couple of pinkies instead of fuzzies until he can move up to the next size the store has,
but keep in mind that it is likely to take longer as pinkies are less nutritious as fuzzies. Also, some people believe it is harder on them to digest multiple smaller items than one larger item. You might try checking around for other pet stores in your area or mouse suppliers within a driving distance that will let you pick up an order instead of paying shipping.