(1) Internet access is "limited". I'll stick with "limited" because it's a mixed bag. It's been 5 years since I cruised, though not Mediterranean and was able to find flat rate per-day, however, the one day I broke down and purchased access I found it to be very unreliable (single shared satellite connection for the entire ship). This is the same for phone service. The last ship I was on had a ship-board cell "tower" that showed up as international and I can imagine even T-Mobile doesn't cover that in their zero roaming considering ship to shore calls were $9.00/minute from the suite. This also encourages my coworkers to think long and hard about whether or not to call me in an emergency.
(2) Everything is taken care of, including entertainment. I find it difficult to relax, even on vacation -- it's an exercise of planning what to eat, when to eat, what to see, what to do and when to do it. When "at sea", the cruise director provides a menu of what you can do and when. You pick. Very little energy is expelled in enjoying myself.
(3) When in port, same rules apply. You don't have enough time to plan some grand excursion, so you pick one or two things to do and head back. I always opt for a room with a window and have found that if the ship is oriented with me facing the shore, I can pick up free Wi-Fi from restaurants at shore for a fix (even when the ship is too big and has to be anchored at sea). This provides for a quick fix of internet and stretching.
Because there are many times of the day where there is literally nothing else to do, I find it's the only thing that slows my mind down. By day 7 or so I'm ready to be home again, and the weeks that follow my vacation are usually amazing. The time spent being forced to be alone with my thoughts results in me returning with new ideas, new ways to solve old problems and just a generally more positive outlook. It's the only vacation I take where I truly get the idea of taking time out to decompress.