Look into Celebrity for an older crowd and higher end clients. We've been to most of these places. Our next one is St Maarten, St Thomas, and San Juan. Its our second time hitting those ports, first time not Celebrity, but its a good trip.
Where you go a cruise is important in that if you pick the cheap one to the one island across the bay and back, its cheap, and has a different crowd. We literally saw (3) brawls and people arrested.
On a nice long cruise to nicer places that cost a little more money that has never happened but sight seeing at your port really isn't a thing... there will be a beach, cabana chairs, drinks, a Tshirt shop, and locals selling trinkets wherever you go.
Celebrity is a nice ship for a older couple and older couple things. There's no water slides and screaming kids running around are a minimum, its like staying in a hotel with a mall, a casino, fine dining, and a kick butt cafeteria.
There is a martini bar for example its metal and frosts over with ice so your drink sits on a chilled bar and they mix drinks like Tom Cruise in cocktail. There are dances and shows and etc.
If you pick a newer ship the carpet will be nicer, the elevators will be less worn out, and etc.
Here is a tour of the Celebrity ship "Edge". We liked it when we've been on it but I think its one of the older in the fleet now. Good luck.
https://www.youtube.com/watch?v=iaH3jvq6IpU&t=19sThis is practically Venezuela (Bonaire)... probably a heck of a deal on that trip now. lol.
(Curacao and Bonaire was a really good cruise a couple years ago actually.)
This is a shot from our room. Having a patio and listening to the water at night while you sleep is worth getting an outer room.