Cullen Bunn being writer, what with his somewhat sketchy, 50-50 record. Even more so because he's made it clear that his Uncanny run will be an extension of his Magneto run. Averted when it comes to Greg Land being on art; people are pretty unified in their hatred of that.
Sabretooth. Either it's great that his being a good guy gets to be explored more, since it was a thoroughly Aborted Arc thanks to Secret Wars (2015), and is a way for his character to gain some real depth. Or it's keeping a plot point that made zero sense to begin with and will keep asking readers to care about a mass murderer.
Draco in Leather Pants: Between the bent of the 2014 Magneto solo series and now his elevation in Uncanny, it's quite clear Marvel is angling to capitalize on years of this to make him the new Wolverine. His role here, which essentially just rehashes Wolverine's "leader of a team of black-ops X-Men" from 2008's X-Force v3, is particularly telling.
Rescued from the Scrappy Heap: Xorn II was originally treated as Fanon Discontinuity at best, loathing at worst for his status as a walking Continuity Snarl. Reintroducing him as a target of the Dark Riders, only to show no fear, calmly offer them tea, share a bit of philosophy then kick their asses and sending them fleeing for the hills made him an Ensemble Dark Horse.
Unexpected Character: Elixir and Triage. Of note: the latter sticks around after he shows up, unlike the former who seemingly gets killed in a tragic manner.
Xorn, due to the massive Continuity Snarl surrounding him and unlike the other two is thus far a recurring character.
As of issue 19 Elixir is back and has teamed up with Exodus to watch Magneto's back.
