The actual roller chain in your model pleases me.
I love how you're documenting everything. We're trying to move to that approach next year. Your process is far above what we're aiming for, and the amount of effort in that spreadsheet is insane. Your tutorials are very in-depth and think outside the box and explain points that the average tutorial-writer would not even thing about; you essentially diagnose and fix problems before they even occur.
You may want to include Vex among your supplier list in the Overview tab.
In your "research" tab, you mention that robots rarely benefit from going faster than 13-15fps top speed. That is debatable.
In the same tab you mention that #25 chain is half as wide at 15mm HTD belt but 1.5x as strong. I think you're thinking of #35 chain.
Thank you for mentioning sensors! All too often we forget to add sensors to CAD models.
You mention that speed and weight are independent of drive style, but I think it's worth mentioning that unless you put a lot of effort into it, a swerve drive will be heavier than the other drive styles (and I love swerve, but most designs tend to be heavier than tank). As for mecanum, I have not found good records of them going over 15 or 16fps, and so you might want to find a solid source for that before thinking that it's going to be as fast as a tank drive.
The stuff about absolute and relative references in spreadsheets is something I did not know, and should prove handy.
I am most certainly sharing this with the members I am training. It should prove to be a fantastic resource!