What you are missing here is the pay issue. Morahs are paid poorly. If you want commitment, it comes at a cost. If you pay pennies, you can not expect a commitment from a young lady whose first responsibility is to get married. If you pay respectably, then you can make some demands.
My mother, a’h, was 4 inches taller than my father, a’h.
She would say “I look up to Daddy”. And she really did. And they had a beautiful marriage.
If all else is okay, height should not be an issue.