ADK

Walls magnetic? Yes
Mini-fridge? Yesish, not really that cold.
Hold a wine bottle? Going to say no.
Reservations for mini golf? No
Doctor and getting meds? Will leave that to someone else for better info. Would say yes, but will need to be seen (pay a fee) and they would provide what they have off hand (cost for the meds and might be limited variety/types)

yeah..I guess leaving the ship around 8am or 930 makes a big difference then ...as does self check out too.....I have never done anything else on any cruise so far.
 
Way more fun being one of those people outside waiting to get in the building then leaving!

It was probably closer to an hour to actually leave the ship and clear customs, with the last 20-30 minutes just waiting outside for our Lyft to show up. Since we were in the next-to-last group to actually leave the ship, there was a huge bottleneck just getting to the point where our Sea Pass cards were scanned. We left from the main theater on deck 4, and even though we had a straight line run to the gangway, there were only two people scanning cards at the exit point. That was at least 30 minutes of waiting, plus another 10 or 15 as we wound our way down through the building to where luggage and the customs lines were.
Throw in an unexpected bathroom pause, and needing a bit of time to find our luggage and for the porter to get it all stacked (I still can't believe he hauled all 8 of our bags on one small dolly!), and then another 10-15 minutes getting through the customs line, we were easily at the 1-hour mark by the time we were actually outside with the crowd waiting to be picked up by their taxi / airport van / Lyft / Uber.
I will say that when we arrived at the port for embarkation day, that was also a little after 11 AM and there were still a good number people standing outside the terminal building exit, waiting for their rides. It actually threw us off, as we thought they were waiting to get into the building until I noticed they had all their luggage with them.

We went on Harmony in February, had a group of 10.  When you exit through customs to the outside, the first people there are RC employees that arrange group transportation, it's like $20 per person to go to the airport if I remember, which is high.  Instead of that, after you get outside from customs, hang a left and walk to the corner of the building.  There is private group transportation there, I believe the workers were wearing red vests.  It is $9 per person to go to the airport, you tell them how many you have and they flag you an appropriate vehicle.  It was super easy.  RC sets up shop on the prime real estate right outside customs, but a 1 min walk farther away and the same transportation is half price.    

Wow......it took that long from 9:30 till 11 am to do all that? I am usually boarding the ship at 11am when I cruise.
I always do the self check out when disembarking and its about a 20 mins process max in my experiences.
 
 

When we departed Harmony in March, there was no longer a porter line. I asked our porter and he said they didn't have a dedicated line anymore. Even so, the porter was worth the tip.  He managed to get way ahead of us in line (no idea how). Customs was easy and the porter completely arranged a taxi van for the 7 of us and all our luggage (it was a squeeze).
Most airlines allow you to drop off bags 4 hours before your flight.  There were a ton of people waiting for the 4 hour point.  We had a 2:15 flight but one of our party had a 2:45 flight. Once all the bags were taken, we took a taxi to the beach for lunch and took an uber back to the airport. 

Uber or Lyft
A RC excursion would offer this.  I'm not aware of another option, other than going to some hotel and asking nicely to have the luggage stored (along with a tip).
You do need to go through customs, although it is pretty quick...unless you get flagged for a more thorough inspection.  If you want to save time with the Customs line, use a porter to take your bags.  No cost to use the porters, you just need to tip them after.  Porters often have their own line.

I don't believe that RC can store your luggage, because you are in the port terminal and it's the port workers handling everything once the luggage is off the ship. I've read other accounts here of people being on the beach with their luggage on disembarkation day while waiting for their flights, so you wouldn't be out of place to be seen hauling your stuff around. The porters definitely won't keep your stuff in any kind of storage, their job is just to get stuff onto the ship and back off into the passengers' hands. Even if they could, you'd be hard-pressed to get back into the terminal without a valid Set Sail Pass or other document.
General information on disembarkation can be found in this post from Matt.
My family and I just did our own first cruise ever, also out of Port Everglades, and disembarkation was very straightforward for us. We had the next to last time slot at 9:30, and we got outside and ready for pickup around 11. The earlier you disembark, the faster it will go since the customs lines won't have built up yet.
I think your group is too large for any Uber or Lyft service to help you out, so you'll definitely need a van service. It might not be a bad idea to check out something like resortforaday.com or a similar service and just make a reservation at an area hotel, have yourselves and your stuff brought there in a van (maybe the hotel's van), and ask the bellhops to store your things in the locked storage area while you enjoy your time ahead of your flight. Then you can just take the van one more time when you need to get to the airport.

I'm glad you brought this one up ADK, we haven't talked about it in a while.
No matter what you might think, RCL wants their excursions watered down. They want all their excursions so that anyone can participate and make tour operators refrain from offering advanced, or faster pace, or more difficult excursions aimed for those who can ride a bike for more than a few miles, maybe are a runner, or otherwise are in reasonably good shape.
Except for the St Kitts Volcano Hike! And for what reason this one is allowed to be so advanced we'll never know. A test of fortitude, stamina, and guts. Less than half who start will finish.
My wife Susie trained on a Stair Master at her gym for 6 months in preparation and she completed it in 2014. Here are some pics (spoiler alert: the video is from the top of the climb....and the view is probably a lot less than you think you have should have earned.) Below is the Golden Ticket, the path and terrain in general what you climb, her shoe back onboard, and finally short video at the summit.
DSCN1543.m4v
DSCN1543.m4v 
 

Yes, when I did the math regarding the amount of time and miles, and that people said it was more of a climb than a hike, I was out, lol. I could maybe do a slow climb or fast hike but not a fast climb!

Yes, when I did the math regarding the amount of time and miles, and that people said it was more of a climb than a hike, I was out, lol. I could maybe do a slow climb or fast hike but not a fast climb!

I can't answer the photo question.  I also buy it at WDW but never have on a ship.
Arcade credit goes on the seapass card so you'd need one for each boy.
There are plenty of hangers.  If you feel you don't have enough just ask your stateroom attendant for more.
 

That is a subjective question. Are you naturally a cold person in restaurants?
It can be windy on the upper decks but in late March only once did I find it chilly where I put on something. I wore a lot of short sleeves or sundresses and I did not find the restaurants or theater cold and I never used warmer clothes. However, my MIL is always cold everywhere and always wore long sleeves. I do bring a light jacket or pashmina in case I need it but this cruise I didn't. 

Thank you! The travel router is great. I'm thinking it would be easier to control the kids' access than Voom alone. We live in a rural area with really bad internet so whenever we're on vacation and the kids discover fast internet that becomes their vacation, lol. 

The iPods would at least help and you could give them to a few people who would tend to hang out together.
Yes, you can share as long as only 1 device is connected at a time.  One thing to look at is a post on page 2 of this discussion page.."using a travel router". It may save you some fights of who is on when. 

Welcome!
I just returned from Harmony a week ago. Great ship and you’ll have a great time.
Your questions were answered but I have a few add-on tips. 
1. If anyone has Apple devices, you can use iMessage for free. There is a well known glitch on Harmony. Put your iPhone in airplane mode and connect to the WiFi “Royal-WiFi”.  We all had iPhones and we easily stayed in communication with each other on the ship and my teens could still text friends at home who had iPhones. 
2. On my day 3 cruise compass, voom surf was $15.99 per day and surf and stream was $19.99 per day. They considered this a daily deal so I’m not sure if it was more other days. 
3. If your kids/teens want to do the arcade, you can prepay for packages on your cruise planner but you can’t buy a credit package on the ship. These prepay packages give you a some free credit. Once on the ship, you pay per game. My kids while weren’t excessive could easily rack up a $15 charge in 10 minutes...each game is about $1.25. I think a package gives you some control over how much they spend.