Thanks again for the replies!

I'm pretty sure I'm going with Animal Plastics. I emailed them with a couple questions and Ali emailed me back within a few hours!

I think I am going to go with the 4 row rack that can hold both 15 and 32 quart tubs which should last me awhile with both snakes being so small and I'll get another rack once they are ready to size up. I already have "ideas" for the two empty slots.
After doing some thermostat research I'm going to go with the Herpstat 1. I'll feel better having a relay just in case something goes wrong.