Tunes vs. songs is actually pretty simple, if the person in charge just asks what's wanted. We had about a 70/30% split, in favor of tunes, as we went around the circle last week. I asked if, next time, we should have two rooms, and split up into two groups-- an advantage of having the thing at home, since we do have the space. We decided on a one-group beginner's jam, a split into as many smaller groups as people want for the second hour or so, and then a final round back all together for farewell tunes or songs before departing. I think the problem is just that people who are leading are not always communicating with the participants-- it's not that hard to just see what people want and then organize around that.
Of course we also have the advantage of being in the formative stage of a brand-new thing here. We have no long-held, rigid ideas about how it's always been done.