We were also on this sailing and share many of your pros and cons for the Prima. Here are a few more thoughts...
Room:
We also were a party of three (47/48/15) in a regular balcony room and when that couch is fully extended, it's no joke how little space there is to get by. Whatever the legal limit is for the amount of space available in an emergency situation, they pushed it right to that limit. I must have hit my knee 3-4 times on overnight bathroom visits trying not to hit my daughter's overhanging feet (she's 5'8"). When the bed was 'tucked in', the room was plenty big for us. Not sure if I missed it, but it would also be amazing to have a nightlight in the bathroom so you don't have to get blasted with full light in the middle of the night.
Seating:
The only places we found it difficult to find seats was the Observation Lounge in the afternoon, the buffet for breakfast and lunch (this room was bonkers) and the pool area in the afternoon. One tip if you have a relatively low amount of little kids on the sailing like we did, the chairs up on the deck with the kid's aqua park were plentiful and it was pretty quiet.
With three early days of rain, the lack of indoor seating in the Observation Lounge was probably to be expected. With more sunny days, you'll love all of the outdoor spots to hang out and relax.
One other note on people commenting about the dirty chairs and couches, sadly they're right. So many of the spots on deck 8 looked really awful for such a new boat.
Galaxy Pavilion:
Fun overall, but by the time we hit it at the end of the week, many of the best games were either broken or not fully functional. For example, the cool VR truck that you've all seen by now, it could be driven but had no motion. Kinda seems pointless. I would also say that about half of the games already have pretty outdated VR. We did the 'Pearl' escape room and found it a bit easy but enjoyable.
Speedway:
Well worth the $15 for a drive, I just wish they didn't throttle our speeds so much throughout the experience. Those things could really move if they weren't being held back. Maybe I needed to try the solo time-run experience.
Food:
Indulge is exactly the greatness everyone is saying that it is.
The Local was awesome for pub food and desserts.
Hudson's was beautiful and laid-back, the Commodore always felt more rushed and loud.
Hasuki was a blast, just don't book here if you have any sensory issues or want to talk to anyone farther away than the person on your left and right.
Layout:
I can't say I loved the layout of the boat. I think I'm pretty good with directions and it took me forever to get used to where everything was. The Prima got me to realize that I prefer the style of mega boat like the RCL Oasis where there's a mall type of atrium where I can get coffee/water/pizza at any time of day.
Bermuda:
If you've never been to their Aquarium/Zoo, I highly recommend it. Lots of great up-close animals and super cheap.
Thanks for reading. 🙂