That guy got off too easily. Let's list his sins: 1. He just wants to beat a guy he doesn't know, because he is just better at doing his job and even threatens others to get to know his whereabouts. He is a stalker. He is an unscrupulous (and bad) liar. And then he wanted to >choke a girl unconsciousness<. WTF? Let's do that. What's the worst thing (with a high probability) that may happen? He wanted to do that, so he he can take her as hostage to finally beat his competition up or worse.
I don't know if he did stuff like that before, but his readiness indicates he did. His incompetence shows, that he never went that far before, yet still, he would have. He already trespassed with violent intention into someones house and needs to be punished harshly. But killing him, seems to be a bit to extreme. He's a little pipsqueak in comparison to MC and won't dare to to anything after that to him. A good trashing should do. Welp, in case he dares to come around a second time, he could still be killed off.
I know it is dangerous to let people targeting someone in a medieval fantasy setting live, but on the other side you can't kill everyone. Then again, he IS a high ranking adventurer, who hunts dragons. Those don't come around too often and might actually pose a threat. ... Hmmmm... Maybe he should be handled indefinitely, after all.