I have about 15 downloaded, but only play on 5 of them regularly. I play on each one for different reasons, and that is why I would recommend doing the same.
GreenTie: I have $59 in bonus to clear there and I really like the bonus structure.
Titan: I have $80 left in bonus available, but I really think the bonus structure sucks. Once I get through this bonus, I'll probably move most of my $ out.
CD: I've recently started to play in the CD Poker Tour, so I keep enough money there to pay my entry fees.
AP: League games and other freerolls.
RVP: A friend of mine has a private table that we like to play at. $1 entry fees.