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A for the vote.
As for duelist specialties. I really like the way the pathfinder tabletop breaks it down. I can somewhat adapt it to this format with a branching tree.
First off stealth is never a duelist trait. A duelist that attempts to strike an unfair blow is not a duelist at all. "counterparry" would be better named "Parry and Riposte" if I'm thinking of your intent properly. Dual wielding is also not a tool of the proper duelist, but could easily be replace with mastery of the dueling scarf/cape. A user of this spins and flips in ways where the cape masks sight of weak points in a Duelists stance, giving a higher dodge chance, and later uses it to hide the movements of her blade, making it easier to slip past an enemies guard.
To replace stealth, perhaps you could have "uncanny awareness" where the duelist is so astute to there surroundings that they cannot be caught "flat-footed" or surprised and off guard.
I could give a lot more info, but this is already a wall of text so I'll wait for you to ask if you would like more input.
