So, on the same vein of actually using DDW to learn to fight, another feature of duellism that would be cool is if during challenges, we don't lose XP, similar to fighting in the arena. The reason for this is because if you continuously lose xp, you have to bash, but if you bash, you get enemied to a place, and if you get enemied to a place, well, you aren't DDW on said territory, so, effectively, if you bash to get your health back, you won't be DDW, anymore.
Alternatively, giving select DDWs, perhaps as a gift or something, can be given the ability to open the arena as, I don't know about anyone else, but I find it difficult to find people to play with.
Anyway, just more ideas.
Written by my hand on the 20th of Springflower, in the year 1313.