Love the show. Its got a great feel. Like the earliest days of radio/TV.
Couple of ideas to throw at you.
Pick a great artist/style to feature. Play their music. Interview someone who specializes in it. For example, you could do a Reverend Gary Davis show, with a phone call/interview with a modern player who specializes in his music or who knew him (reminiscent of your talk with Sandy Paton). Maybe a call to a Roy Bookbinder, who was a student-friend of Davis'. (BTW Roy is also a friend of both Pink Anderson and Robert Lockwood Jr. the still-living-and-playing octegenarian step-son of Robert Johnson). Or you could do a mountain ballad show and have a phone call with Ginny Hawker (for example). She's a singer and school teacher from Elkins W. Va. Beutiful voice, knows the music from its source, teaches at Augusta folk-music camp in the summer.
The mudcat community has people who know who's out there preserving and recording in tradtional music that might be able to get you in touch with these people. Wally and Sandy come to mind off the top of my head.
There are also some musicology professors who play and research this music in the field. They might be willing be part of a pre-arranged interview.
Programming like this would be more along the lines of the original pre-forum/pre DT Mudcat, i.e. educational, and thematic.
What do you think?