I think it's an unpopular opinion generally, but I do love a musical episode. Subspace Rhapsody was particularly good because the characters could tell they were singing.
I used to dislike musical episodes, but I've either changed or have just grown into them. Figured I'd instinctively dislike Subspace Rhapsody but I enjoyed it a lot.
Yeah, the in-universe self-awareness of them singing was definitely a factor in making it successful (IMO, anyway). Now that I think about it, the other musical episode I really liked (Scrubs: My Musical) was also self-aware in that regard.
Maybe it's just the aspect of people breaking out into song randomly without explanation or acknowledgement is my issue with musicals 😆. They just need the proper framing device.
It starts off a bit campy in the style of the movie it's based on, but even early on there are serious moments that set the actual tone of the show.
The show is very human for all its outlandishness. It's very much a 90s/00s show meant for the YA crowd, so go in with that in mind and it will still hold up.
The thing that would've really sealed it for me, I think, would be if we got the occasional cut away from the musical number to the parts of the ship that weren't affected. Like, there's one bit where someone shuts off the artificial gravity for dramatic effect, and I was dying for the cut across the ship to the guy in who's been off-duty taking a nap for the last three hours, slept through the whole first act of the episode, just drifting out of his bunk and into a bulkhead with no explanation. I love a good "consequences of everyone being just a little too Extra™" in my self-aware diegetic musical episode.
My partner usually rolls their eyes when a musical episode gets going, but has rewatched Subspace Rhapsody with me multiple times. It’s all in the execution, and SNW did a great job of it.