In which ways might your life be different if your mother had had your father’s personality and he had had hers?

Not much.  My parents had very similar personalities.

I probably would have not been born.

WOW.  My mom would have beaten me with a belt?  Nah.  

I wouldn't have been born.
My mother removed her Dutch cap without telling Dad about it.
(She told me that her cap had always worked perfectly; she had never conceived unintentionally.
He told me I was a love-child, an accidental conception.)

Dad, as a woman, would have asked her lover whether he wanted to be a father and would not have conceived without his knowing.
He was immoral in some ways but in things like that he was punctiliously honest.

Mum's deceit was one of the primary causes of all the suffering that ensued.

My parents were always like rabbits, so most likely nothing would be changed...  :)