So Aaron has created plenty of problems for Thor. The hammer is sentient, Thor is unworthy, Jane holds the hammer, and Odin is basically evil. But all these problems can be fixed by explaining why Odin is evil. What I would do is say that the Ones Who Sit Above in Shadow survived, but need the Asgardians to move on to the next cycle to continue to survive. So since there isn't another cycle to return to, they take Odin and begin to replace him with what the Odin would have been in the next cycle. Except this Odin is not the benevolent All Father we've come to love. Slowly throughout time the current Odin is successfully replacing the old Odin. The new Odin wouldn't have made a worthiness enchantment, because he's a jerk, so to fix this a new origin for the hammer is made. Now this hammer is sentient and prefers Jane over Thor. No one notices that this is happening until Beta Ray Bill's hammer disappears from existence, because only the classic Odin could and would have made such a weapon and there aren't many Mother Storms to replicate the current origin. But Bill's bond with Stormbreaker is too strong so he sees through Those Who Sit Above in Shadows lies and recruits Thor (and Jane if she still has the hammer) and they eventually face down the new Odin. They stop him and Those Who Sit Above in Shadow and everything is restored, Jane is unworthy and Thor can lift Mjölnir, Mjölnir is what it's always been, Odin is restored, and Bill has his hammer back. So that's how I would undo Aaron's madness. Thoughts?
The only way I really think this can be adequately retconned is not by more story telling with this group at Marvel. I see this new Marvel as creating something like a New-52 for 616...you know, ultimately people are going to want the original many worlds of the old DC back, and slowly but surely it will creep back somehow. I see the same for Marvel except for one major major issue: Marvel is owned by Disney.
Disney won't budge from the current social trends in anything they own because they need to make money. Bucking against the social trend will jeapardize that profit.
Disney will ONLY allow the retconning if the social trends change.