Mixed sessions are my favourite too, Mo. I'm happiest accompanying songs and singing harmonies, although quite content with tunes and unaccompanied song. We get that sort of session over in Beverley. Often fringe sessions are singing only or tunes only, and that's fine if that's what people want.

Ideally what you want is tune players who sing a bit, and who know how to accompany songs (other than by just playing the tune the singer has). And not the kind of players who insist in accompanying everything by dragging it into an adjacent key. And if the songs can be interspersed with a neat set of tunes, that's great.