The Color Purple was a pretty amazing musical. I'd love to see that live and it's really the only musical I've seen and liked. Other than Les Mis but I put that in a very different category
I would kill to see Lion King. Iโve seen the broadway singers singing the opening in airports and wow! Well, videos of them just kinda bursting into song? Looks phenomenal.
A Final Fantasy game! I just don't think it has a strong enough following in the West. Video games are still a little niche despite their explosion in popularity within the decade.
I find it honestly pretty funny that most of what everyone is answering are shows still within their peak commercial relevance so you can just go see them if you keep your eyes on your nearest performance art space. You're going to see it Off Broadway, technically. But they're super available shows.
Update: I'm meeting Alex Brightman and Erika Henningsen (Among others, but these are the two i have photo ops with) in a few weeks and Alex is my inspiration and BJ is my dream role and I'm so fucking nervous but excited and ahh