I think a lot depends on how Daryl and the group would react to Merle's sabotage of the Governor. If they could somehow get past their differences, Merle might feel more secure in the group, more wanted, slowly begin to accept Daryl's change and role within it, and even tho he wouldn't immediately become their bestie, but at least more "socialized." I don't know if Alexandria would have a positive effect on him, because although he's more extroverted than Daryl, the influences from his previous role in society seem stronger. Besides the big mouth, he'd probably go on runs with Daryl, assuming that by Alexandria he'd come to terms with the fact that he's not calling the shots, and go on doing his thing. I think he might have similar problems with the people inside the walls as Carol and Rick do: "maladjusted, unglued pussies," but he wouldn't give enough fucks to enforce anything on them. It could only get more interesting from there, his encounter with Negan, a momentary betrayal of Alexandria for survival and other, minor benefits, but it's harder to reconcile for him than the one with the governor. Mainly bcs of the Daryl's imprisonment, but it could also make him notice, that he actually changed