The reason they give for the Hulk being able to stand up to Black Bolt is that he is, as of WWH, angrier than he has ever been. That's straight from Greg Pak, the writer of the whole event since Planet Hulk. Also, the warp core explosion somehow interacted with the Hulk's physiology to make him even stronger than usual to begin with. That's also from Pak. So he's got a higher base strength than his usual class 90-100, plus he's angrier than ever. I think those two factors make it perfectly reasonable for the Hulk to be kicking as much ass as he is.
Granted, that explanation will probably fall flat when it comes to Strange, since no amount of physical power should really be a problem for Strange. But Pak's done well enough so far that I'm optimistic he'll make the Hulk/Strange fight at least kind of believable.