Peterson is perfectly fine for who he is. He's pretty much the blueprint for Holmes, albeit with Holmes you expect a better starting point and better results. With Peterson, compared to his time with the Mets, his Ks are down a lot (8.34 to 5.92 per 9), his walks are down a little (3.97 to 3.08 per 9), his xERA, FIP, and xFIP are all worse...and yet his ERA is over 2 full runs lower. Mostly because his BABIP has dropped 96 points. Throw the ball in the strike zone, and let our defense take care of the rest.
With Cabrera pretty close to being stretched out, I'm guessing he pushes Assad back to AAA and we see if he can find a next level in short bursts. Things have probably gone pretty wrong if he's starting a playoff game, but that's a good problem to have when a month ago, SP depth chart wise, it would have been like, Will Sanders.