I'm about to try my first attempt with kisslicer (I want to like Slic3r but I just can't get acceptable prints out of it). One note: your support structures inconsistently fail to handle changes to the "elevation" param. I raise the elevation as my gears often interfere with the belt clamps and only some of the support pieces adjusted correctly.
The other options that I checked seem to work just fine (checked groovemount, hex_base_nuts and a few details in the motor mount that I prefer to be different).
I agree with you on the weakness of the "on the back" orientation of the guidler teeth (going back to much older comment complaining about your changes). Very curious to see how your idler compares.