I can kill off Rey or Leia quickly, even in a Dooku/RG team using QGJ lead, Lumi, GS, RG, Fives.
Either you already have endgame gear on all your DPS toons and/or RG, or you haven't met the new Rey, yet.
16.5K health + protection with 142 armor. You do not have the firepower to consistently take out Rey without waking up RG, unless you are already buffed (or unless your DPS toons have end game gear). And if you claim you took Leia out, first, RG is already taunting. If you debuff him with QGJ, you will again trigger him trying to kill Rey. Your description doesn't make sense.
And with your team, using QGJ to do the buff in round two to down Rey without triggering RG, that means it's already too late. Because without end game gear, the new Rey will usually either kill your QGJ/GS or her team will down your RG close to the end of round two.
Plus, how does RG usually stun Rey in the first round? Sometimes, maybe. She will have Foresight by then, a lot of the time. You're saying your team can kill leia and still have an attack to waste to remove foresight on Rey before RG's first action?
The new Rey is noob-slayer supreme. But in this case, noob is anyone that has been following the current meta but has not yet gotten the end-game gear. I am not sure what her counter is, yet, but I'm working on it.
Again, I don't think this is a balance problem. I just think due to Rey's mechanics, she is a very good toon to gear up, first. Once the bell curve catches up and most top teams are geared up, she will no longer be a major factor.
If your team is all-else equal (meaning gear and abilities), then there's really not any OP toon, I know of, yet. Except maybe Leia.. but she's P2P, and she's still beatable (I believe she Will stil be beatable at endgame). So no big deal, AFAIC.