I think Patina Miller would make a great Papa Ge. She proved how sinister and powerful she can be in Pippin, I think she'd do the role justice. I'm not sure she would ever replace, but Cynthia Erivo would probably be a killer Papa Ge as well, as would Headley.
I would love for Asaka to continue being portrayed by a male performer, and Titus would surely be wonderful, but I can't be the only one who wants to hear Jennifer Hudson sing this role. It's not really a deep role acting wise, I think she'd be able to pull off the characterization just fine. Imagine being the person in the seat right next to her when she belts that note right in their face?? I'd spend $120 to be in that seat for that moment alone...and not that it would ever happen (and probably should never happen), I would kill to hear Jennifer Holliday tear into Mama Will Provide. I don't think she has the physicality for the role at all, but just imagine her slapping her Holliday-isms all over that song.
To me, Kenita Miller is the definitive Mama Euralie. She brought so much depth and beauty to that role, I'd watch her play it 30 years from now. As others have mentioned, LaChanze would be lovely in the role, if only for nostalgic reasons (same applies to her in the role of Erzulie).
I personally loved Q. Darrington as Agwe more than I did Norm Lewis, which I found surprising. Would Joshua Henry make a good Agwe? He's got a killer voice from the audio clips I've heard, I'm just not too familiar with him as a performer. Physically, he's perfect for the role.
I would love for newcomers to continue being cast as Ti Moune. The role has given us LaChanze and Hailey Kilgore, maybe we can keep getting some phenomenal talent out of the role.
Philip Boykin is one of the loveliest people I've ever met, let him play Tonton for the rest of his life. I wouldn't have a problem with it. He's wonderful.
And Patti Lupone can be the little girl in all future productions.