But you don't need to stage a festival for this, Toblerone - one can have sessions anyway. And there are a number of "song and ale" type events around the country that would typically attract 200-300 participants.

A festival is more than sessions, more than concerts, more than ceilidhs and dance displays - it is all of those things, happening concurrently and providing synergies. Some examples:
- the "star performer" in town for a concert, who will join a singaround in his/her off-duty time, giving an opportunity to others to hear him/her without going to a concert.
- the ordinary (yet excellent) singaround singer or instrumentalist who will be heard by more recognised performers and agents.
- the unusual song or tune that will be heard in a session by recognised performers and agents, giving the song or tune a chance for a wider audience thatn just that one session.
- watching a dance display for a few minutes (even for someone who is not dance-oriented like me) feels good and adds to the spirit of the occasion

And so on. When you go to a festival you hope not just to catch a few performers or have the opportunity toi sing a few songs/play a few tunes yourself, but also to sample the general atmosphere, and perhaps see/hear something that is our of your ordinary experience, that might energise you.