the hubs are radiused, you can see it in the pic, albeit not all that well, its standard practice for all machining.
I didn't do the sprocket hub because its already so thin it was only gonna ounces instead of lbs. as the hub only weighs one lbs. raw.

the distance from center of rotation has other variables that can work with or counteract, one being traction, another floatation. a lighter and closer to center 20" hauler for example, will give worse race results than a heavier and farther out from center 22", and the difference is dramatic, been there, done that.

 

Sorry Chris, I couldn't see it in the pics, maybe from a side shot. Still I would suggest leaving a little extra. This is just my opinion that for a couple ounces you could probably double the strength of the hub at that point. I'm not sure what would happen if a rear hub broke but I wouldn't want to be on the bike at speed when it happened.
Amen on the 22"s. 20"s work well in wet or dense sand.
I'd like to get a set of wave rotors for lighter brake discs. just another 3 hunks of rotating weight.

 

the new 04 model hubs look a lot lighter, might have to price some or get a weight on them.