How about the ability to “defect” from your current faction to join another one? This happened in several TNG episodes (I’m sorry I don’t remember the titles of the episodes in question). This could be a great way to get more players for the Klingons as my only excuse for not playing a Klingon up to now has been too little content and too much PvP.
So I’m thinking like this: lets make it several missions that both factions can go on like the weekly series and while playing them we get a plot that could explain why you would want to defect to the other faction. At the end of the series the reward would be to decide if you really want to defect or not or you could pick another reward that is more inline with what we’ve seen from other weekly missions.
You should also get to take all of your BOFF’s with you, however, I say you should have to pick just ONE ship to take to the other faction with you. Once you have defected, then you can only get the ships that are available to that faction. And yes, you should still be able to use the one ship you took with you.
Further more, I would like to suggest a kind-of mini game where after you join a fleet, you have to earn their trust to stay in the fleet. It should be some kind of badge or emblem that only the fleet department heads can give to you and you have to earn a set number before you can become a full member of that fleet.
In theory the idea is great. However, I don't believe it would have the desired effect for the Klingons. Feds have no reason to switch over (except wanting the best melee weapon of the game). I think there would be more players who level a Klingon on the KDF side and defect to the Federation with a bird of prey.