Imagine those people were Toris
You mean something like this?
if so, supported.
Would look awesome!
But how would you show differences between a 9th and a 10th Dan? Writing numbers on it?
How would you show from 1st Dan up?
I would say make it a buyable item like the custom belt.
Do an add on with the already custom belt in the shop which goes for more adding the belt texture. But having to earn it?
Thats my two cents