Firstly, my x axis end stop switch wiring was too short. When the bed was down really low, the cable would pull tight and lose all of its slack. I simply wired in an extra 150mm and sealed it all up. Now I can use the full z-height without worrying that the cable will be pulled out or snap.

Secondly, the wiring on the back of the unit is a trainwreck. I used some tape to group wires going to/from similar locations together. It's still not pretty but it's a hell of a lot neater. This will help with coming up with an electronics cover design (if Solidoodle don't release the official STL which it looks like they won't).