I think the only plan that gives any points for the AY leisure flights is Finnair Plus (their FF plan). I know QF excludes these flights (despite being otherwise generously giving 100% credit for all fare classes on AY). Better decide soon, no retroactive credit (so you must sign up and nominate the FF plan prior to taking the flight). But the points are the least of your problems, you do realize that AY uses a special high-density seating configuration on these flights, with very small seats (and something like 29 inch pitch, so legroom is non-existent). The AY charters to the Canary Islands are quite famous for being flights from hell (presumably the BOS service is more civilized).

Edit to add that I forgot to mention that BAEC isn't really an option for you as you cannot join BAEC flying discount tickets -- you must fly a flight on Y or higher fare before BA allows you to join their FF plan!