As kino as it would be if Eren wiped everyone's memories and left them to start families - think Falco and Gabi, maybe Reiner and Pieck, all getting to enjoy the fruits of his labor - I don't think we'll have a mindwipe ending since the Ackermans that survived persecution as a result of Kenny's actions would be immune from its effects.
So how will the different allaince members act during the final controntation? I think Armong is going to be mindbroken harder than Reiner so he won't matter. Mankasa is probably going to stand up to Eren for the first time and get crushed for her troubles.
Manlet would be the most interesting one to watch, in my opinion. I think he'll actually choose to settle down with Hange and willingly let go of any desire for fighting he might still have left as it would make for the most kino end to his arc. Eren's fight has a purpose beyond vengeance, right now manlet's doesn't, and a major theme of the series has been breaking cycles of anger and hate to make way for something better - a stable marriage and family. Manlet and Hange, like Eren and Historia, will therefore likely have a whole little league baseball team's worth of kids.
