My Dooku counter is Yoda's Battle Meditation in my case. With the QGJ speed he goes first and this way I can protect myself from stuns, DoTs, Speed downs, etc for 2 turns, which is when usually the AI uses the specials. With all my 5 chars being able to attack is easier to take down the other team, I usually attack the ones with assist attack first and leave Dooku for after I've dealt with them.