Yes, as @Ethan5956F said, between modified VRC legal 393 replacement gears (276-2487)(info), V5 threaded mounting inserts (276-4840), vex standoffs, and HS shafts which could be turned on the lathe (example), you can already get all this functionality from the VRC legal parts.
Allowing to get simple inexpensive mounting hardware from the local hardware store or an online retailer would be a good thing, because not everyone has access to lathe or expensive CNC equipment.
Those parts will, probably, give you less than 10% performance improvement for the price of investing twice as much time into tinkering and doing engineering research that is more like the real world (i.e. searching online for the appropriate COTS parts, evaluating if they are cost effective vs machining them yourself or using vex stock parts, etc…).
I would say it is a win from the educational standpoint.