Just have Traitors be on a team, traitor vs. traitor is lame

[Spy_Guy]

also how often do spymasters actually find the other spymasters in spy anyway

Not that often, because the policy appears to be "KILL EVERYTHING THAT MOVES except my guys"

Having traitors get other traitors as objectives means that they themselves are never free from looking over their own shoulders, which I think is alright.