I think it's not easy to say, Sandman. I'm familiar with all his songs (as I said on the other thread) and they fall into many categories in my humble opinion. They're:-

-comic songs (eg 'I Wear Horn-Rimmed glasses')
-chronicles of rural life (eg 'Following the Binder Round')
-social commentary (eg 'Oi Can't Get a Nice Loaf of Bread')
-nostalgia (eg 'The Old North Walsham Line')

But principally I think, they're celebrations of Norfolk life and the Norfolk accent and dialect. (eg 'Hev the Bottom Dropped Out?' 'Hev Yew Gotta Loight Bwoy?' 'Moind Yer Hid' and so on) I think this category is the most important one.

Taking all this into account however, I'd say he was a folk song writer.
Having lived in Norfolk in the sticks for forty years now (and I love the place), I find his songs enchanting and poignant.