I guess I'll answer your questions by saying it gives CIS vibes because it's using the same model as the CIS Jedi Hunter and it's KOS. That could have easily been a job from the CIS faction. Again, I don't know what kind of roleplay you would be doing with a Jedi Hunter droid other than commanding your droid to attack a Jedi and say, "GET HIS ASS!!!!!" That's not roleplay. Mavelle's example of RP is really nice. That's exactly something I was going to suggest hunters do. Y'know, be smart when dealing with Jedi and spring a trap. However I'm confident if you remove the Hunter Droid from that situation and just have the four hunters, you CAN take down a Jedi. Of course it's going to be difficult, it's a Jedi. Most Hunters I see dealing with Jedi just fight them on the wide open ground where there's plenty of room to force leap away as a Jedi. If you say, lure a Jedi into a trap, like the caves or inside Aurek base, maybe even blow the entrance so debris collapses and blocks the entrance, spring an actual ambush, you will kill a Jedi. You guys still have perma weapons that will blow through the health of someone. And if you're not properly planned or equipped, then why are you trying to kill a Jedi?
Now I know that Jedi want to fight more saber users, myself included, but attaching CIS droids that are KOS and are, y'know, droids, to the Guild doesn't make any sense lore wise. Why would Dooku give his droids out to the Guild when he can simply use them himself? He wouldn't risk the technology getting into the hands of the Republic by giving a supply of Jedi Hunters to the Guild. Like what would stop the Guild from making them Sith Hunters and get a fat paycheck from the Republic instead? There are a lot of questions I could also ask but I think I get the point across.
In me replying to this post for the past five minutes I have already thought of a what I believe to be a better idea that still has some of the issues I have with Jedi Hunter, but completely negates the three massive problems I have with your suggestion:
1. Weird lore implications
2. KOS
3. Provides very little or no roleplay
I call it the "Guild Duelist" These are members of the guild that are trained with a vibrosword (reskinned single-hilt saber, no force powers, sort like the training saber) They have been honing their ability to combat melee users and as such, are able to combat even saber users. I would absolutely love to roleplay as this character. The amount of ideas in my head are getting me excited. Imagine talking with a Jedi about your stances and how similar your training could have been and relate to them. Or Sith. Or whoever! A lot of possibilities here. I'm not going to list down what health, armor, ROE, stances, or whatever because I know some asshole will just debate it and ignore the rest of the points I made when balancing this role is not my job. I'm suggesting the idea of it.
I think this would be a very fun addition to the Guild that makes roleplay AND gameplay exciting for everyone. My points still stand and my opinions on Jedi Hunter remain unchanged, but if you use my Guild Duelist suggestion or make something akin to it that doesn't have the three problems I have with the Jedi Hunter, then I will happily support that.