We were on the Majestic for 14 nights in May and have to agree about the theatre entertainment. I know Princess doesn't do this as well as other lines, but this was dire and I said so on the survey.
I put it down to Covid and staff shortages; maybe it's harder to find good acts right now, but I feel your pain. For us, the Cruise Director & staff at Live were excellent so we went there whenever we could get a seat. Odd layout, took a while to get the hang of it!
Also a vegetarian and I agree about the vegi meatballs. I was so excited to try them and ew!!! Enough said.
Having never sailed Royal Class, I really thought I'd miss the full promenade, and I did a bit, but it wasn't a deal breaker. We also sail Celebrity, and there are things we like/dislike about both lines, but overall we had a fabulous time, loved the ease of the medallion, and we've booked on the Royal in September.