Don't get this 'ambitious' factor honestly. I do think he should move, but does it make him any less ambitious if he stays at Villa? Accepting the demands and ideas of the project and being the star player of his boyhood club? I think that would be quite ambitious of him to stay and believe he can reach new heights with Villa.Grealish is entering his peak years and he is incredibly ambitious and still wants to improve.
If the decision rests with the player then he will be soon be wearing Blue.
The reality is obviously different, but besides the point. Don't think majority blues here or elsewhere will be gutted if he doesn't come, just a thought though.