Only surfed at Avalon and fancy giving sailing a go there. Where you guys launch from? Just wondering with the reef stretching across the bay.
Here's my take on it.

Mark's correct in that when there's good seabreezes it's normally flat. but when you get a >2m SW swell it can be nice
There's a local guy down there named Pete. Ask him for some tips on where to launch from and etiquette down there.
He's always more than happy to help.