Leiter lacked command and when he can't spot his FB, he's in trouble.
I think he has limited upside because of his age and frame, he just doesn't have it to get stronger or add even a bit of velocity.
So it comes down to refining his secondary pitches and pitching backward, and maybe learning a new grip and developing some movement on his FB and sinker.
But he has pitched well when fresh, so he could be effective in a long relief/spot starter role where you limited his innings.
Arano seems to be regaining his velocity, he may push Garcia for the setup job. Garcia has picked his game up this season, he has the FB, slider and splitter, but lacks consistent command. And his 2/7 save/save opp ratio says he doesn't pitch well under pressure. He should be better, but he'll be 31 next year. Arano was hitting 94, touched 96 and his slider works well off his FB. It'll be a good battle next season.
Neris can drive you crazy, but he's steadily improved, hard to knock 20 for his last 20 save opportunities.
Ramos has the lead, Rios and Pinto will probably start in Lehigh but both have the stuff to be top flight RPs down the road.
I can't decide on Alfaro, one AB he looks very good, then he whiffs on two straight low breaking balls with Herrera on second. Comes down to whether Stairs can reach him and get him to be more disciplined, it's not a matter of walks, but working counts and getting pitches he can hit, because he can hit FBs in the K-zone, he has to learn how to deal with everything else. Altherr is a good example, he went from a wild swinger three years ago, to a more disciplined hitter with a shorter stroke who laid off bad pitches, now he's an even more patient hitter who keeps his hands back and can hit breaking balls. Williams has shown continued progress all season, though he still has a ways to go.