I have recently re-watched Kamen Rider Decade with
tiuneo and after that, I realized why I could not remember a thing of what happened in the series: from all the Kamen Rider series I watched, this one was the least remarkable of them all. I think I can consider it my least favorite (after even Kamen Rider Gaim, which I really, really disliked). The fact that I did not remember a single thing of what happened during the series before I re-watched says a lot about it.
Perhaps the moment in which I watched the series does help with the way I feel about it. I decided to re-watch Decade after I watched Kamen Rider Fourze, which happened to be my favorite KR series so far. I believe I can list all the reasons why I didn't like the series:
1. Tsukasa is the equivalent to Lightning in Final Fantasy 13. He looks pretty cool and badass at first, but after the, say, 5th chapter, he gets tiring and repetitive. He really feels like a character that the creator loved so much that he wanted him to be the strongest, coolest, most handsome of them all, which ended up giving birth to an overpowered character. He doesn't have any depth whatsoever, nor any character development. What kind of development can a perfect character have?
2. The entire series kinda feels like a fanfiction. I honestly did not think that each Rider universe had a particularly good story. In fact, most of them, perhaps with the exception of the Black and the Black RX, were very shallow and boring. The supporting Kamen Riders were weak and their personalities were lacking, even if you did not compare them to the original universes.
3. The girl characters are awful, specially Natsumi. Natsumi has to be one of the most useless characters I've ever seen in a KR series. She doesn't have a personality on her own, nor one that helps with any other character's development. She's in the story mostly to serve as a damsel in distress and run in circles, doing absolutely nothing to help.
4. The acting is awful. Masahiro Inoue, in my opinion, is not a good actor. His acting skills are similar to those of a potato. Natsumi's actress, to be honest, is almost as bad as him. I'm not exactly sure if that's because of Tsukasa himself or if she as a character is just so lame that even if the actress was top-notch, Natsumi would still suck.
5. It has no ending in the regular series. If you want to know how the series end, you have to watch the movie. And, to be honest, the W/Decade movie is almost as bad as the rest of the series (to be fair, W has a pretty cool arc, but Decade is as awful as the rest of the series).
6. It repeats the same joke. A LOT. Seriously. That finger stab thing gets old in the second use, but they still insist on using it during the entire series.
So, in the end, I'm actually glad I'm done with the series. At least now I can move on to the next one and hope it gets a bit better than this.