I think that’s the best thing going for SNW.
Not every episode has to be about something. In fact most of them aren’t, they’re all one-offs. They go to a thing, some problems happen, they solve those problems. It can be thrilling, scary, intriguing, or silly.
None of these grand arc stories where every moment of every episode is so important that if you blink you’ll be lost for the rest of the show. None of these “very special message” episodes either. Just random space adventures most of the time. It worked in the 60s and it’s working today.
Anybody who went to acting school has some background in music and dance. Obviously not their best talent or else they’d be a singer instead of an actor. I often consider that most people on television can sing and absolutely knows how to dance, we just never see them do it.
Sweeny Todd is a good example of this. You know almost the entire cast from something else and had no idea they were capable of doing music all this time. But, a classically trained actor has definitely been in a musical before, we just never knew about it. Alan Rickman wasn’t exactly a vocalist, but he could keep up with one.