Eovaldi- Pivetta- Wacha- Hill- Houck
Whitlock-Barnes-Diekman-Brasier-Taylor-Strahm-Sawa-Davis/Hernandez
Not very deep. If 42 year old Hill tweaks something, things get dicey quickly.
Yeah, I agree Whitlock is best off being a mid-game stopper and inning-extender on close games. Especially if Cora and Bloom are on the TBR "times through the order" philosophy, which they seem to be.
If you look at usage, Eovaldi and Pivetta are going to reproduce 2021 and be "classic starters" who will go as deep as they can, 30 starts a year. Wacha was signed with the same expectation, but has a shittier track record in terms of ERA in recent years. Hill's going to be a starter too, but, as you say, age. I'd guess they treat those two like our last two fungible starters - pulling them early if there's trouble. Then Whitlock/Houck for the last spot.
Deciding Whitlock/Houck - last year, Whitlock gave us 73 innings. Then Ottavino at 62, Barnes at 54, with Sawamura and Taylor just after them. Otto is gone, Barnes may be broken, and Sawamura seemed to finish ragged. That's about 300 core innings from the bullpen to address the starting style.
I can't see trying to get 5 innings out of Whitlock and turning to Houck to take his role. So, Houck to start, Whitlock in the pen.
I'd expect Diekman to be a 60 inning go-to guy after Whitlock.
Taylor will chip in 50.
Strahm is a lottery ticket de to his knees, but like Whitlock could be folded into the rotation in an emergency.
Much turns on where Barnes and Sawamura are.