Mr. Happy's comment about tune sessions takes us into a different area. New tunes are nice, but people can't join in until they've been played enough times to get into the brain and out through the fingers. And you go to a music sesion to play.
And most musicians are better than me; but I have difficulty starting off a new tune that no-one is joining in with, when I have all the other tunes ringing in my ears.
I like the old 'lift the roof' standards, dotted through the evening. With the new and fairly new ones mixed in.