There's room for more than one high-leverage arm in the pen though. Obviously they didn't bring Storen in to save money on Osuna - they brought him in to pitch 60 high leverage innings. But now that he's here, they might as well save money on Osuna.
Agreed, but the only way it's even a remote possibility is if he saves 40 games. If he saves 40 with a 2.5 ERA, you at least have some internal discussion.
It should be Storen, and the order should come from the front office. You save arb money on Osuna while at the same time giving Storen the best probability of being in a position to turn down a QO.
He missed most of the year because his shoulder didn't work, then came back throwing 90 with a <7% swinging strike rate. People are probably scared he went John Danks.