Would be up for a small reward of xp (not so worried about gold) on the duel servers again, although recently I've been saving my dueling for when I hit level 30 (when i tire of the grind to 31, not to mention the obvious benifits of being "max level" in a duel setting) and I'm not really fussed not having one.
On the kill reward and TK penalty. Personally I don't think this is nessecary but I would be up for a reflective damage system of some kind. I think the old version highlighted the problems with a kill-reward system and even if its a token amount i think it still encourages people to be detrimentally kill hungry. I also think a severe cash deduction for Tking is a little harsh, particularly in modes like siege where its harder to avoid hitting your teammates. Reflective damage strikes me as a more pratical way to discourage reckless behaviour, although i am aware of the problems this would throw up.