Toaru has good concepts, world building and character dynamics but the execution sometimes leaves room for improvement. The author has a sort of ad hoc writing style where he’s basically writing all day and just jots down whatever idea/aesthetic/vibe he’s feeling in that moment. As a result, he expands on some of his ideas to an autistic esoteric degree while other interesting concepts end up being a footnote because the author forgot about them or didn’t care to do anything with it; and there’s not much consistency in that regard. This is also why the overall tone and setting ranges anywhere from “pervy high school romance” to “apocalyptic SCP containment breach”. There’s also the obvious issue of lazily done tropes and fanservice which are tangentially related to this. The index anime is also widely considered a mediocre adaptation of the source material, so that probably contributes here.
The thing with Railgun is the author’s creative vision for it ended up changing a lot from how it started off. The premise was originally “spinoff about a cute marketable waifu that fans like” so it was very low stakes, fanservicey and slice of life in the beginning. Season 1 is an adaptation of these early chapters + filler so that’s the overall vibe there. It actually ended up being a lot more well received and commercially successful than the main series though and at that point they decided to take it seriously as it’s own thing.
Railgun Season 2 is definitely the peak of Toaru anime adaptations, the whole arc is very high stakes and engaging. It expands a lot on the protagonist’s character and her personal frame of reference in this world, along with her relationships with the people around her. The events that unfold throughout the arc are very consequential and significant to her on a personal level and I think it does a good job of making you care about what’s happening. It’s definitely a step up from the content of the first season in a narrative sense. The animation and production quality is really good too, a major step up from the adaptations prior to that. I would definitely recommend watching at least the first 16 episodes (the remaining 8 are filler and skippable) at some point if you had some baseline interest in the series but didn’t like the execution.
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