Thing is, many third parties count towards mafia numbers when jointing is taken into consideration, so in terms of setup balance I think it wouldn't be too overpowered since often it's not really creating another mafia vote.

Perhaps if they only could act toward a single 3rd party per game, as too many traitors would maybe ruin it. Just my thoughts.

If he tries to convert a townie, they should not only lose their converting ability, but the townie should also get a message saying "You were almost recruited last night!"

jointing rarely happens though :P or at least in all the games I've played nobody has been doing any jointing with eachother...so *shrug* I upped it anyway though

Way too over-powered. Needs to either not-kill or perhaps when it hits a Townie they lose their converting ability the next night.

One major use of this of course would be to help prevent any backstabbing when maf try to joint with a third. Could also be interesting in other situations however, eg. with cult, do you want to get your old mafia member back on your side or do you hope they'll cult you? I can also imagine some interesting setups involving a spy perhaps, or possibly a fool where town have to work out whether he got traitorized or not and therefore whether they can lynch them.
Also, looking for suggestions, should Recruiter get a message saying that they've converted someone or not?