Joe,
Did you ever see the episode of the Andy Griffith Show, where Barney Fife joins the local choir?

As far as the loud, or inexperienced Bodhran player is concerned

1 - The singer should have the option of saying no "drum", or no "accompaniment" on this or that song.

2 - whomever is facilitating the Session, should have the clout to do that as well.

Speaking as a non-musician, who has to STRETCH his ears to hear one singer among 6-8 guitars and 2 bodhran players and a fiddle. And this from only 8 feet away!