I'm sorry, but to me there are certain hymns and certain tunes that go together ... and this is one of them. As you can see there are various ways the same tune can be sung - but it's the "proper" tune.
We used to go to a Church where the minister was always altering the tune - he said it made you think more about the words ... I could see what he meant, but in my case it did the opposite, as it just made me annoyed!
So, what do you think? Proper tune - or a variety to make you think?