The rules of addressing a couple really need to change. Most people have reached a point where they will address a couple however the couple chooses to be addressed. Unfortunately, there are many people who bang on their etiquette book and shout about the proper way. "Mr and Mrs Hisname Lastname" is not always acceptable.
The incorrect assumptions about wedding etiquette need to change, too. There is no part of etiquette that says a ceremony must be *this* and *that.* Many people feel that it is wrong etiquette-wise to deviate.
I had never heard of the shower rule that a family member cannot host until I read on here. It's never been an issue in my area.