I have grown up a Saints fan, but contrary to what many believe, I do not like drafting Saints players because I want to root them on without having to think about fantasy points. This year is my first yr having a Saints player on my team (Colston) because the league format I am in is heavy toward WR's.
My opinion: Brees
Romo has a running game and Romo has a decent defense on the other side of the ball, which in turn could lead to more running plays called in order to eat the clock.
Brees has a running game as long as Deuce is healthy. Bush can't do shit without another RB to complement him. Deuce gets hurt every season (seriously, I do not think he has logged a completely healthy season since entering the NFL in 2003). Pierre Thomas is more than capable of carrying the load as well as Stecker, but Payton won't give them the chance. Payton is an ex QB coach, so he has a pass heavy mentality. One of the things that drives me completely insane about Payton's shit play calling is that he passes on 1st down often. Whether it is complete or incomplete, we run on 2nd down either as a short yardage play if prior play was complete or as a misdirection play if prior play was incomplete. We fail on our 2nd down runs for the most part meaning 3rd down is another passing situation. And a small amount of the time, we will pass on all three downs, which uses 1:00 of the clock for our entire offensive possession because Payton sucks donkey balls. Also, Brees has Shockey this yr. I'm sure Shockey will pull a Deuce and get hurt early and often, but Brees targets his TE more than any other QB over the last half decade or so.
All in all, it is a toss up as I think you will get your production from both Romo and Brees, I vote for Brees because he is a bigger part of his offense, which is a pass heavy offense, where Romo has Barber to hand off to.