I would like a workhorse type for the 5th starter. Someone who can pitch at least 6 if not 7 innings, even if they give up an extra run every couple of games or so. No more 5 inning starts. Maybe that can take some of the pressure off the bullpen.
Sounds like John Lannan?
(And I don't know why the team did not make an offer to Jackson, unless Rizzo and Davey decided that Jackson was simply not as good as they wanted. He was unpredictable: brilliant, then bombed, then brilliant, then crushed...)