It seems to me a better dynamic within Christendom is engendered by the following emphasis.
1. Christian first.
To be Christian is to a) take Jesus of Nazareth as in some meaningful sense to be the Christ, and b) attempt in one’s thoughts and actions to follow the teaching of Jesus of Nazareth.
In short, being a follower of Christ ought to be first, as far as one’s identity vis a vis Christianity goes. Everything else is secondary. Which isn’t to say secondary differences aren’t important – they are.
2. Denomination second.
So, one isn’t a Mormon, rather one is a Christian. One isn’t a Methodist, but rather a Christian.
Only secondarily is one a Mormon Christian, or a Methodist Christian, and so on.