Kazmir wasn't as good as Lackey or Rivera this year, but I think Kazmir's comeback was a little more impressive. He was getting lit up last year in Sugar Land (who plays in an independent league). His velocity returned and he posted respectable numbers (especially in the 2nd half, where he had a 3.38 ERA and 82/17 K/BB in 72 IP). Not only did his K/9 go way up (almost back to pre-2009 levels), but he posted the lowest walk rate of his career at 2.7. He's an intriguing free agent.
The 93 ERA+ isn't great by any means, but with the way his 2010-12 seasons went, it's a lot more than to be expected. He looked like he'd never pitch in the majors again.