I actually liked this one, I can see why it's more divisive and it's definitely not a normal episode of the show. It's a little messy and did feel like it was restrained by its runtime, but I think it was held up by a some strong scenes, a few good jokes, a decently well done heart of the episode I think some can relate to on some level, and its use of music.
I also agree with the sentiment this season has had better than usual side characters I'd actually like to see come back in the future. Mr. Nimbus and Planetina were both very different than other side characters in the show, and both actually pretty likable, and despite only being in one episode each, feel like they have more potential and interesting established relationships with the main cast to have them to appear again.
It'll probably have its split of likers and dislikers, but I'm happy they did this episode personally.