Kai Leng is a quite lame boss. He has better skills in cutscenes than in actual combat. To make defeating him more satisfying his combat should be modified. He only rushes with sword and sends electrical waves. In letter from Hackett we have informations that he uses same implants like Phantoms, who are really challenging. I suggest to change his combat style to make him a phantom with additional powers electroslash and shield boost as he normally has. I don't have any programming skills, so I leave it to some skilled mod maker.
What's your opinions?