That's cool, very functionnal. Yes it appears we got the same idea and that was to keep the adapters off that threaded portion of the stub axles and tighten everything up. Not to long ago, I also tried to make my own stub axles that have no threads. This would've simplified the process since the only thing needed to be done to the adapters would've been to drill through with a 6 mm drill bit and then it would've slid on the stub axle with no slop.
I decided to stay with the way I did it at first because I now use Summit shafts on my Revo and I just don't have the tooling to machine a threadless stub axle with a CV style joint on the opposite end.