This post is old, but I thought I would share what I have been working on. I have been trying to create a perfect grid for my JM QCW that will work across all of the individual pieces and allow for modular fences and hold-downs to work. I am using the 20mm holes, but it would be easy to adapt to imperial rather than metric with one parameter change.
I decided that I wanted to have both dog holes and threaded inserts so I have the flexibility of either plus the t-track as well. Here is a screen capture of it, if anyone is interested let me know and I can send you the CAD file (Fusion 360 or STEP).
