The specific nerf reasons will be Professor X’s Master Plan and Hulkbuster’s Overdrive. However, Demiurge has shown over and over that they vastly overnerf. When they could have fixed Sentry just by changing WR to 12 AP, they nerfed all 3 abilities. When they could have fixed Surgical Strike just by reducing AP gain, they nerfed X-Force as well. When they could have fixed 4Thor by simply reducing charged tiles on the Blue, again they nerfed all 3 abilities.
Kingpin’s not going to be heavily used, but doesn’t look amazing except with SW. However, even if SW gets nerfed, I can’t see her passive countdown tile going away.
Depends on your roster, but probably Hulkbuster since he’s newer, and you can actually get 3 covers relatively easy. At 1/1/1 most players won’t realize the power of Overdrive for some time. Either that or save for the rest of your 3* roster.
I’ve already got 7 PXs and 5 KPs, so IMHB current cover availability isn’t an advantage. And my 3s are in pretty good shape. It’s more a question of which one of those 4s should be getting my ISO. I guess the problem is that until we see what they do to PX, it’s hard to know.