I'm irrationally high on Weaver, he's going to be a 4+ win pitcher this year and I refuse to acknowledge arguments to the contrary.
I’d be concerned about his innings. He’s never pitched more than 140 innings in a professional season.
In fact, that would be my concern for the whole starting pitching staff other than Martinez. You’re going to need 800-ish effective innings from starters other than Martinez. You’ve got a lot of guys either coming off of injuries, or are young and unseasoned, or both.
Seems to me like a cheap, reliable inning eating starter with a contract like Vargas just signed with the Mets (or even cheaper) would be a good way to go for some insurance for the Cards. Nolasco, Jimenez or Hellickson are all out there as possible pick ups. Unsexy names to be sure, but they might look a lot better in August after Wacha gets pulled in the fifth inning for the third start in a row, Reyes has an injury setback, and Flaherty and Weaver start getting worn down as their innings pitched get into the 140s and 150s.