I love some of those hymn tunes, despite the dubious sentiments of some of their words. I like the idea of claiming them - or reclaiming them, in some cases - for non-religious purposes and putting (or restoring) secular lyrics to them, a sort of Vaughan Williams in reverse. Many of the tunes have the melodic structure of simple folk dances or songs and fit well into the traditional repertoire, possibly because they were traditional tunes long before they were hymns.

Existing examples:
All Things Bright and Beautiful: The 29th of May.
Be Thou My Vision: Banks of the Bann
To Be a Pilgrim: A Blacksmith Courted Me
We Plough the Fields and Scatter: John Barleycorn

etc.

Marje