Or could another big event have sufficed?
Now, I would like this to remain objective. I know that some people like Miles better, some Peter and some just enjoy both. I don't want anyone saying he needed to die because they like Miles better or anyone saying that Peter didn't need to die because they like him better. Now, bias aside, I think it could've been done without killing Peter, if done creativly enough. We could've moved Reed Richards' return to UU sooner.
So, Reed Richards comes and attacks. Europe is mostly destroyed. This is a huge event, causing mutants to band together to form the X-Men again. The Ultimates, X-Men and, yes, Spider-Man go to stop Reed. They do, but now the entire world is not only frightened of mutants but super humans altogether. With Peter's already ruined reputation (at the hands of the Chameleon twins), the Daily Bugle is no longer enough to stop the whole world from attacking him. So, Peter is forced to go on the run with the X-Men. With Spider-Man no longer able to protect New York City, Miles becomes a new vigilante and starts to fight crime.
1) This would provide us with the "on-the-run" book of X-Men.
2) This would be a status quo change for Spider-Man, sending him on the road with the X-Men, replacing his old title with Miles's.
3) This would relaunch the UU, so as to have three ongoing titles.
4) This would make both Miles and Peter fan boys (I think) very happy.
If you think Peter needed to die, vote above or just say he did. If you don't think he needed to, vote above or say no and provide a way it could've played out differently.