The playoff pitching logjam is really interesting. My recommendations would generally adhere to the Fangraphs "depth charts" projections (which blend the two leading projection systems, ZiPS and Steamer)
SP (4)
Peralta (3.85) - Clearly still their top SP despite the inconsistency this year. Last couple starts have been interesting with better efficiency and ERA but decreased strikeouts. Not sure what to make of him right now but you have to run him out there as the top guy
Montas (4.21) - Longest track record of MLB success, and has been great since they traded for him.
Myers (4.41) - This is where things start to get interesting. Least experience, but most consistent performer since the beginning of June.
Rea (4.63) - Actually projects a little worse than Civale, but has been a much bigger part of the team and has pitched much better than Civale lately.
RP (9)
Locks (6)
Williams (3.02)
Megill (3.50)
Hudson (3.82)
Koenig (3.94)
Payamps (3.95)
Civale - Most teams like to carry a long man for blowouts and emergencies, and my guess is Civale has the leg up over Wilson and Ross for that role
Locks if healthy (2)
Mears (3.49)
Milner (3.64)
Both have bad ERAs, but great peripherals which leads to their good projections. Milner has been a big part of the team and is a useful matchup guy to have in the playoffs
Wild cards (1-3 depending on health of Mears / Milner)
Misiorowski (3.95), Ashby (4.06), Hall (4.08), Peguero (4.10), Yoho (doesn't even have a projection yet)
Totally depends on who is throwing the best down the stretch, especially which one(s) get up to the big leagues and pitch well there. May only have room for one of them if Mears and Milner are healthy and still looking good, but any of these guys could have a big impact