Captain Universe powers and could kick the ass of Morlun should he show. Why doesn't he just go kick Morlun's ass then? Because his Captain Universe powers are tied to that universe and when he leaves it he's just another Spider-man. Also we see that 616 Peter is "The greatest of them all" because he defeated Morlun before.
The interactions between the various Spider-men and women are fun, but this crossover is already getting a bit out of hand. Things are rapidly becoming confusing even for an old hat at this like me. Mind you, it's a fun story so far, but the way it's laid out doesn't help a premise that can easily become a mess to begin with. Why does the main story start here and not the main mini series coming out later this month. With any even the main mini needs to be the backbone of it and all others are (ideally optional) tie ins. Also I didn't care for the main universe Peter to be "The Chosen One", I would have preferred it if he was just another soldier in this war. Part of the brilliance behind Marvel numbering it's main universe 616 is that it's just another world, not Earth 1 like at DC. And really? In no other reality did a Spider-man defeat Morlun? In all the trillions upon trillions of universes of the multiverse?
I like this event so far, but Dan Slott needs to be careful here, this could quickly go off the rails, and if that happens the novelty of tons of different Spider-men as well as the nostalgia factor of revisiting eras and spin offs of the franchise won't be enough to keep this afloat.