I'm not Catholic, but the 3 things you listed (women in priesthood, gay marriage, celibacy) are the main reasons I don't necessarily agree with all rules the Catholic church has. And I'm not saying this in a way to bash anyone's religion, I just don't agree with it. But those would be the 3 things I would change, especially women in the priesthood because I am a woman and I don't really understand why it's not okay for a women to be a priest, when there is tons of female pastors.
Also some changes with accepting birth control, which would be difficult.
