Just a suggestion for Day 3/4. Consider heading to the Dogs for a snorkel and then head to Leverick to stay two nights. Get a rental car and go out to dinner - Coca Maya is a favorite of my wife's. The next day, visit the baths, copper mine point, other sites as desired and stop at Hog Heaven on the way back. Have dinner at Leverick at the restaurant upstairs (or if you are lucky enough that this works out to be a Friday, enjoy the BBQ). You could also as you have time take the free ferry over to Saba for drinks.

Days 5-7 you could stop at Fallen Jerusalem (another favorite of my wifes - great snorkel spot with features like the Baths, but usually empty), Marina Cay, Monkey Point then Jost Van Dyke before heading back to the base..