Hi jrh20 and welcome back from your cruise. A couple of observations about some of your observations:
1. It sounds like you were surprised by the extra things for which you paid on your trip. These should not have been a surprise. Before you booked, your travel agent should have explained what's included in the price, what is not included, and how much the "extras" are likely to cost. There are some cruise lines that are actually "all-inclusive" of drinks and tips, and even a couple that include shore excursions. Of course, these cruise lines are a lot more expensive than Royal Caribbean.
2. In general, it's nice to tip for good service, just like on land. The three people whom I feel are the most hard working and deserving of tips are your room attendant, your waiter and assistant waiter, plus anyone who has given you special service. I've never heard of an assistant room attendant. Bar waiter tips are always included in the bar bill each time you sign one. I'm not sure from whom you purchased food onboard and left a tip? Are you talking about the specialty restaurant? Most people give a couple of dollars to room service waiters as well. Again, there are suggested amounts for tips that you should have been told about before you booked, so you would know what to expect.
3. We have had a lot of discussions here about cruise ship food. There are those who love it, hate it, and everything in between after all being on the same cruise. I hope you and your family were able to find some things you liked at each meal. I often find the food too salty.
4. ALL of the potable water you encountered on the ship, other than bottled water, is sea water put through the ship's desalination and filtration system. That's typical of all ships. This includes tap water, water from which coffee, tea and reconstituted juices are made, etc. I'm not sure what was the problem with the coffee on the Promenade but I hope they fix it!
5 & 6. Sounds disappointing!
7. I'm not sure what you're saying about the workout facility. Are you sorry it wasn't more crowded after Day 1? At least hopefully you didn't have any problems getting on the machine(s) you wanted. Spa services are money makers for the cruise lines, so I'm sure you had flyers in your room every day advertising the spa and the various shops onboard.
8. Poor internet connection is very typical of all cruise lines. When you're in the middle of the ocean, the ships all use satellite connections to the internet, which are exceedingly slow. This is especially true during the more popular times to use the computer. It's very frustrating compared to what we're used to on land. All cruise lines charge a high per-minute rate, but packages are usually available that allow a slightly lower per-minute rate. Then, of course, you have to guess at how many minutes you think you'll use during the course of the cruise, and if you have minutes left over, that money is gone anyway. A lot of people choose to wait until they're in port, and go to an internet cafe, which is always much cheaper and usually a must faster connection. Most ports I've visited have internet cafes that are walking distance from where the ship or tender come in.
8. Agreed! I love the ice shows. It's amazing what they can do on a small rink.