Other Things That Could Have/Should Have Changed....
The McFly's house. We have to figure that George has a much better job and more money in this timeline, so wouldn't they have a nicer house in a better neighborhood.
Marty's room. Even if they were still in that house, Marty probably wouldn't have recognized his own room. Since he grew up in a very different, and probably more positive environment, his personality would be different (like his brother and sister) and he would have different things around his room. Plus his parents had more money, so he probably would have had better stuff.
The ages, number of, and possibly even the names of the McFly kids. Its been discussed on other threads that wouldn't they have considered naming their eldest son Marty or Calvin. Of course we don't know the reasoning for going with Dave/David. Could be a family name. But the possibility of his middle name changing, or Marty's name now being Calvin Klein McFly exist.
Marvin Berry keeping the idea of Johnny B. Goode for himself.
Marty dating Jennifer. Again, different childhood environment, different personality. Maybe they aren't as compatible this time around.