Not going to lie, the utter hilarity of Cable potentially becoming the new Apocalypse after devoting a sizable portion of his life to being the dude's ultimate nemesis would make that outcome fun on a level I can't really describe. Also, his dad was sort of Apocalypse for a while, though that was more possessed than heir.
Honestly, this sounds kind of terrible. But in a way that it might actually be really good if done well. It's just hard to imagine it done well. I will remain patient and wait to hear more.