That is a great machine and is similar to the type of design I plan to build. To that end I have a few questions about your build:
1) What was the reason for the leveled epoxy under all the slides? With the care you took building the pieces I would have thought the Birch would have been flat (or is it for strength, other?)
2) The epoxied in inserts you showed, the holes were 1mm larger than the insert with a semi-cured epoxy coating? And these were stronger than the tapped sandwiched aluminum plate?
3) I noticed along the way that your spindle bracket was beefed up (as I see many others do as well). Was this from a performance observation or just a precaution?
4) I know you checked for flex early on, but now that you have used it for a while is there any area you see as a weakness?
Thanks for sharing your project.