3) Chase Silseth
As of now, Chase Silseth would presumably be the favorite for the fifth starter spot in the Angels rotation. He certainly deserves it with the way he pitched down the stretch for the Angels. However, Silseth only made eight starts this past season and it's very possible that they'll decide he needs more seasoning.
If the Angels do nothing else, the most likely scenario is they have Reid Detmers, Patrick Sandoval, Griffin Canning, and Tyler Anderson locked into rotation spots with the fifth spot up for grabs. Silseth might be the leader of the pack to earn that spot, but that's not to say guys like Suarez, Plesac, and others couldn't steal it.
The Angels clearly see something in Plesac which is why he got a MLB deal from them. The deal is saved with the fact that he can be optioned, but it certainly feels like he's going to get every possible chance to outpitch a guy like Silseth and earn a rotation spot.
It'd be rather unfortunate to see Silseth lose his rotation spot if the Angels don't add a much better starting pitcher than Plesac, but it's hard to know if adding a frontline starter is even in the cards for this team. This signing doesn't guarantee that Silseth loses his spot but it certainly puts him on notice. The fact that he can be optioned down to the minors without risk of losing him certainly means something.