I assume most people mare with the intent to grow. Not stay the same or get worth.
I assume most people discuss that while dating. If they don’t, they are retards anyway so who cares what they do.
However when making a personal change that will affect your spouse I agree that it must be done with his or her permission.
Permission? You don’t need permission in a marriage. There are no veto’s. You need to talk about things and take one another’s interest into account.
And you make it sound like these are big bold decisions. Like the guy comes home from work one day and says from now on he is only going to shul on shabbos. Or she comes home one day, rips her sheitel off and says she is never wearing it again. That isn’t how life works.