I would say some drier bedding and maybe a few extra holes, you can always cover some if you make too many. More air moving will help dry things up and maybe bring your hot end down a few degrees. Did you have your snakes in something else before? if so I would think to get them back in there till you make sure everything is worked out in the new racks. Plus isn't 4" height kinda short? I'm aiming to have a month between finishing building my enclosures and getting my snakes so I can learn a few things about tweaking my specific setup. As to it looking smaller the measurements probably include the overhangs on the side so you actually get a bit less usable space then is listed in the dimensions.