Since my last update to the project I have made several changes:

1) Y-Lead has returned to a belt until I design a stabilized dual lead setup
2) The project has made it's way into it's final enclosure
3) The project has moved on from Marlin and into Klipper due to ease of changes in printer configuration
4) I have developed a custom interface for the project which will be opensourced in a couple of weeks. It is a native application developed in Qt that runs on the host and is focused around touchscreen interactions.