If I could make an alternate universe of TBBT, it would be like this:
New members and some ex-members who should've stayed
A guy who would be Emily's lover
A woman for the new son of Beverly (possibly)
A few family changes and additions
A new wife and mother for George Sr, and George Jr. and Missy
A new wife and mother for Alfred and Leonard (possibly)
Beverly has another son who would be in Leonard's place and Mary would have two other children who would be in Georgie and Missy's place, one of them could be Katie from the unaired pilot.
IMPORTANT NOTE: And with my dislike of Sheldon and Mary growing bigger and bigger after watching the Season 4 finale of Young Sheldon, I’d be happy this time not to have him in the group. Or he should be a semi-main character.
In a set of stories which aren’t comical, I’d have him not in the group.