#3 A fresh pool of opponents
Jon Moxley has spent many years within the WWE system. A lot of people have asked through the years what it would be like if he were to take on say, Kenny Omega or even someone like Jimmy Havoc, who has a similar hardcore background.
Even if he were to take on someone like Chris Jericho once again, it would be a very different rivalry from the one they had over 'Mitch', the infamous potted plant. Both characters feel a lot bigger and a lot more important than the underwhelming feud we were subject to in WWE.
Moxley has a lot of money right now and an artist to his core, his objective right now is to tell compelling stories. He can paint on a blank canvas in AEW, if all goes well.
Because let's be honest...do we really want to see another Ambrose vs. Rollins program as we'd inevitably see in WWE?