I have very few complaints about this show. If I have any, it’s just going to be in comparison with the visuals/music of Gavan but that’s A: always going to be the case for “Space Sheriff”-styled Metal Heroes shows, which I believe this is the last of em, and B: kind of unfair because this has a lot going for it otherwise. Actually the music in this is pretty good, but it’s no Akira Kushida, so there’s a limit to how good it will be.
What makes Spielvan stand out are the characters. It’s a meatier, and a more dynamic show because it’s not just hero + female sidekick and one-dimensional villains. It’s hero + female hero + female hero who is being held captured by the villains, of which there are a LOT and they are pretty much all great. Basically a lot of badass female characters on both sides of justice. Not the least of which Machiko Soga. I feel like every show that has her as the villain is automatically a better show than it would be without. Her commitment is just second to none. I put her on the same level as having Kenji Ohba as the protagonist. Speaking of the protagonist… Hiroshi Watari is someone I don’t have strong feelings about, but Spielvan as a show is less reliant on him than Sharivan which is why it didn’t ever bother me.
I also don’t remember a lot of episodes that were duds, which Juspion had quite a few of. There’s a good variety of goofs, just monster of the week, recurring character-based plots that wrap up in a satisfying way, and weird new elements being introduced throughout like Dr. Bio being reduced to a floating, talking brain with googly eyeballs and basically EVERYTHING involving Mickey Curtis’ character and his time-traveling, talking, but otherwise completely normal ass looking hamster. Maybe the action isn’t super inspired, but the set pieces become snappier and they change stuff up ever so slightly every couple of episodes so you don’t get too bored with it (again, looking at EVERY Daileon fight in Juspion which I endured mostly because of the theme song).
Also I can't 100% say because I got too bored to finish Sharivan and Shaider, but if you did and you get around to Spielvan, it might feel like a "metal heroes greatest hits" remix kind of show? Curious about that, but on its own I loved it.