Oh boy... for me it is NO CONTEST!! Cruising wins, big time.
Posters so far are steering you right. If you are looking for so-called total relaxation, an all-inclusive may be your best bet. Stretching out pool or ocean-side with the cocktail of choice in hand is just loverly and some people can do it for days on end. Sure, activities and entertainment are offered, but the entertainment is usually akin to productions that could be staged by the people in your office in their off-hours. It's generally too warm to really enjoy non-water-based activities. Water sports can be deceptive, too. Resorts list all kinds of great "toys" but you often find they have very limited supplies of these toys and that your use of them is extremely restricted and/or by appointment only. Booze is plentiful and after lots you don't even miss the quality.
Then there is the food. We had our first (and last) all-inclusive experience last year with family who do this annually. They raved about the food at our resort being sooo much better than other resorts where they'd stayed previously. It scares me to think what they ate in those other places! Imagine the worst cafeteria food ever. The specialty dining options were marginally better, we were eligible for 3 nights in these. Waters smiled charmingly and took note of our special request (including one "no potato, please, due to allergies) and brought out cookie cutter dinners as they came off the kitchen assembly line. No request was ever met.
We like lots of entertainment options on vacation and lying in the sun is something we enjoy as downtime, not fulltime. The resorts are beautiful, ours no exception, but after 48 hrs my husband and I could have cheerfully come home. We were just bored to tears. Normally I want to cry at the end of a vacation - only this time they were tears of relief!
Oh yes... our other family members are off to this year's all-inclusive today. We wish them much joy, and are so happy not to be going along! Our ship sails on May 2nd.