Personally I think something like a "Salaryman Persona" would be awesome. Could be some young graduate joining the workforce.
Like Zoom 100 before the zombies:
It would offer a nice change of setting, some new themes they could tackle and it would still work well with the calendar system since you still have to go to work, have deadlines, meetings, office flings, other activities you can do after work on on weekends, etc.
But to be honest I don't think Persona will ever leave High School. The Japanaese audience (and weebs) absolutely adore the Highschool setting and seemingly can't get enough of it. Expecting Person to leave highschool behind is like expecting The Elder Scrolls to leave medieval fantasy behind. The best we can hope is that someday they make a new franchise or spinoff like Metaphor that changes things up.
Yeah I know.
I'm just saying that I understand why you'd insist on a specific design if your character actually has a personality and dialogue and backstory, etc. I get why FFXVI or Xenoblade go with a specific MC design.
But a game like Persona or Dragon Quest? If the whole point of having a mute main character is for them to serve as a blank slate avatar for the player, then it doesn't make sense to me why you wouldn't let the player create their own character. Maybe back in the day it was more of a technical limitation, but these days that's hardly the case.