Spend a little time in Cruz bay and then decide if you will visit the north side or south side - both are nice but depending on conditions, one might not be as nice as the other.

On the north side, go in and see the annenburg (sp?) sugar mill.. South side there's also some ruins too.

Pretty much all the anchorages are great stops - much quieter than the BVI too. Having never done it, I'd probably spend your time stopping at the anchorages on the north shore - just head east after cruz bay.. Stop at Hawksnest, cinnamon, maho..etc