I agree with Stever. Vick has a ridiculous amount of upside...if he stays healthy, and we've seen that it is as near a guarantee that he'll miss some time during the season as you can get. And while Flacco is a good real life QB, he is not a fantasy starter.
Oh, and do yourself a favor: don't trade away Fred Jackson for Bowe and Wells. Bowe is a great talent, but has a mediocre-at-best QB situation in KC, and Wells is an injury nightmare. Jackson had a freak injury last year, but it isn't something that nags a player constantly, like ligament damage. His broken fibula is completely healed, and he should be an excellent option at RB this year.