Bermuda is the one place where ships excursions can be skipped.
St Georges. Go to the beach. Tobacco Bay, St Catherines both have facilities ,Achilles Bay (100 yards from St Catherines) has privacy and nice snorkelling . Visit Ft St Catherines , walk around the historic town , take a carraige ride , take a glass bottom boat ride/tour.
Hamilton. Shop. Visit Cathedreal and government buildings. Visit Aquarium, botanical gardens. Go to caves, glassfactory, lighthouse. Go to the beach, Horseshoe Bay is most popular.
Try snorkelling with Jessie James Cruises (located in Hamilton) their 4 to 4and a half hour trip has 3 very different snorkel stops at an island, two side by side wrecks, and a great coral reef. Use public transportation to get around. A multi day pass is good for buses and ferries.
Dockyards: Mueseum, shopping, dolphin encounter, snorkel park.
Island is safe , folks are friendly . Go out at night and visit pubs in St Georges and Hamilton.
There is a street celebration, Wednesday nights I believe in Hamilton.
You'll never do all this in one trip so book anoher cruise for next year, Bermuda is a fabulous place to visit.
By the way, Michael Douglas and his beautiful wife , Catherine Zeta Jones live in Bermuda and she is often seen shopping downtown.