Looking over things I think the stuff I'd have a preference for not happening (other than the aforementioned) would be Galactic Storm and Onslaught (but seriously- who wants Onslaught?)
Also would have to deal with the very complicated history of Wanda Maximoff, which I think would just mean eliminating the Whizzer (what a name) thinking he's her father.
And of course we all know what I think about modern Marvel.