I love nothing the way I love a good story.
I think he’s become—at least superficially—a radically different character, but I also 100% support that choice. Here’s why:
Dude’s a teenager. Developmentally, he’s at an age where his identity is going to be in massive flux no matter what—a lot of adolescence is about literally trying on people you might want to be, and committing headfirst to each permutation. In Morrison’s run, Quire starts out as someone who carefully avoided questioning who he was—or much of anything, really—and then, when something pulled a block out of that tower, it sent everything he’d though of as defining him crashing down. His response was to explode—to blindly push back as hard as he could.
So, in Wolverine &, yes, he’s pretty different, but he’s different in a way that makes sense in a logical arc. He’s made a series of grand, dramatic gestures, but ones that were pretty much doomed to failure from the start. He reacted like anyone does when the borders of their world disappear: threw himself outward, hard, to try to find the new ones. If there’s one thing that’s come up again and again and again about Quire—originally, and in the new version—it’s that dude desperately craves security. He’s attached to the bombastic enfant-terrible persona, but he’s happiest in situations like the Jean Grey school, where he can push back as hard as he wants and be reasonably confident that he’s not going to seriously hurt anyone.
In those respects, for what it’s worth, one of the reasons I buy QQ’s character arc from Morrison to Aaron is that—at least superficially—it reminds me a lot of myself as a teenager.
Also, bear in mind: No one really knows how the fuck Quire’s powers work, or what their limits are. He literally stopped existing in the material universe for a while. He’s gonna grow up to be host to a functionally omnipotent cosmic force.
That is some crazy shit to deal with when you are still figuring out how to be a person.
TL;DR - Quentin Quire’s characterization follows a pretty believable arc, because adolescent psychology.