I used to use the Child's river launch in Falmouth. Should be fine for your 22.
http://www.falmouthmass.us/hmnewsite...0landings.html
Vineyard sound has always been a great place to fish. There are several ledges/shoals that hold fish. Just troll up and down them for blues and bass. Drift into deeper water off the ledges to jig for fluke.