Questionable character - Guion for sure. I think he also advocated releasing Quarless immediately, didn't he?
Injury history - Abbrederis has to be at the top of that list. Shields could be there too. Neal, Perry, Bulaga. Lots of candidates here.
Age - Kuhn, they have a replacement available anyway
Performance - any non starter. Guion, Masthay, Palmer, R Rodgers, Adams. The first two might be released, the others merely demoted.
Releasing James Jones would be just the opposite of what you want to encourage. This is a guy who is always available, even when injured, and never complains. It's not his fault he is thrust into more of a role than he is suited for.