Good shout Nige. Plenty of little bits and pieces off white passage to have a poke about in and loads of pretty stuff.
As you say, Goatchurch would be an option, but there are loads of other caves in Burrington. If you've got access to a copy of Mendip Underground, have a look in there for inspiration. I plan to have a look at Lionel's Hole soon, which is also in Burrington. Sounds like a good trip in Mendip Underground.