Not bad, but do you have a flex spot so you can start all 3 RB's? I wouldn't recommend benching Forte and would actually sit MJD before I'd sit Matt. Mathews is probably a good play with as bad as KC is, but if SD gets up on KC and starts running the ball, I don't seem them pounding it with Mathews, but turning a lot to Tolbert too (who looks like he'll play). Forte and MJD aren't involved in committees and on most Sundays I'd start both of them before sitting one of them for Mathews.
As far as your WRs, a lot of people aren't sold on Green yet -- for good reason -- but he's the top WR for Cincy and Dalton's favorite target so far and he's bound to get the most targets this week, especially if Simpson doesn't play because he's a drug dealing bonehead. Besides, how many continuous weeks can Devery score on a big play? The odds are eventually going to deal him an off week, especially the way Brees like the spread the ball around. I think Green is your best bet for your third WR slot.