My anniversaries thus far have been VERY anti-climactic.
On my first anniversary, my sister scheduled her bridal shower, and since my wife was the MOH, we didn't even spend that day together. My sister's reason for scheduling that day: "I figured you wouldn't be doing anything because it's your anniversary."
On my second anniversary, we were unpacking a U-haul from trailer to U-box because the trailer was due back and we had just arrived in Houston.
Anyways, on a cruise, the NUMBER ONE piece of advice I would give:
Never, ever, ever, ever, ever, ever, ever, ever, EVER buy ANY of the excursions through the cruise line itself.
You will spend twice as much for half the experience. EVERYTHING you are offered through the line can be done on an island for MUCH cheaper.
Talk to the locals, ask them where the best [blank] is and what they would recommend for [blank].
Part of our trip was to Turks & Caicos on our honeymoon, and we got in a cab and said, "Take us to the best snorkeling area."
We stayed there for HOURS and the only other people to show up in the area we were in were the captain and some locals. It was awesome.