For me, I think the context of starting pitching (or what 'slot' they should supposedly to go into) should come down to what your immediate opponents are fielding (might change next year cause its going to be a balanced schedule)
Your top 3 for Yankees are Cole (3.05), Cortes (2.74), Severino (3.11); all with 1 WHIP and under 4 FIP (only Cortes is above 3.5 FIP, at 3.62 FIP)
Your top 3 for Rays are McC (1.73), Kluber (3.58), Rasmussen (3.11); all with 1.1 WHIP or less and under 4 FIP (only Rasmussen is above 3.3 FIP, at 3.7 FIP)
Sox are injured, I don't even know what their starting rotation is going to be once everyone comes back lol - Sale, Wacha, Eovaldi would be their top 3 I guess?
That'd make Severino (I think Cortes but we'll just go with stats), Kluber, and Eovaldi (3.16 ERA, 4.53 FIP, 1.1 WHIP) the 3rd starters?
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Berrios' 5 best years (so ignoring this year): 3.74 ERA, 3.79 FIP, 1.15 WHIP
He's close (at least in a sense better than Eovaldi) and I remember Twins fans saying that when he's off, he gets blown out - so maybe he does get QS with most games, but the one or two odd starts, he completely unravels.
So if he gets to that level again (where he reduces his FB rate and increases his GB rate back to norms, HH% drops back to norms - his HR/FB is up 4%, oof), he can be a definite 3rd.
This year, I am not sure yet. He needs to put up a string of QS to even sway the needle. He's probably the 4th this year at this moment (I trust Stripling more than I trust Berrios).
Also, keep in mind, his confidence completely dives into the abyss when he's crumbling. He looks lost and can't seem to reel it back in.
He isn't like Kikuchi where he straight up doesn't trust his stuff anymore, but when he's giving up hits/runs/walks, he starts taking ages between each pitch like he's just not sure what to do.
Maybe we do need someone like Jansen with him to anchor him when stuff is going south, but that trepidation would suck as your #3 in postseason.