Been to Key West a few times.
1) Yeah, there's only one or two "big" hotels / resorts down there. You'll get better bang for your buck at an AirBNB or little hotel. You can do tent camping on a little beach on one of the keys further north if you are into that.
2) There's really not any beach either. The southern coast has a couple of thin ones, but they get crowded quick.
3) The shipwreck museum is kinda cool for about 90 minutes of entertainment. Key West was once the shipwreck capital of the world (something like 1 boat sinking per week).
4) There is a "glass bottom" kayak tour that is pretty cool. They take you out to some of the mangrove islands that will be future keys eventually.
5) The Dry Tortugas tour is OK if you are a history buff, but kinda "meh" otherwise.
6) Seafood restaurants are really good though. Everything usually caught that day. Plenty of places to drink yourself into oblivion.
7) Plenty of good fishing charters down there. Best thing to go there for.
