I think adding Littell wouldn’t hurt. If everything works out perfect and the young guys are throwing well, he has also done long relief before.
Beyond that, the other names you listed I’m not certain are upgrades. Giolito is I THINK, but the others I don’t know.
I am excited to see the young pitching overall in the rotation.
Also, just generally, if they truly were thinking of Festa as a starting option I think that was naive at best