[Matrixbeast]

Decade was actually the first series I watched from start to finish.
While I attempted to get into Kiva and Faiz prior, I was stopped due to either boredom (Faiz) or more boredom (Kiva).
I actively enjoyed Decade because it was bright, it was flashy, and it was a new experience. Only through watching Double as it aired, in addition to watching Ryuki and finishing Kiva after the fact did I see how much Decade got wrong. It wasn't until my viewing of Kabuto did I see Decade's greatest failings.
It was too afraid to show Tsukasa as anything but "In control." Seeing the "Perfect character" Tendou, I saw the similarities between the two, and I saw how they missed the point in developing Tsukasa. They were so concerned with showing off how "Cool" Tsukasa was, they forgot what made Tendou endearing to begin with wasn't his power, his attitude, or his skills. It was his interactions with Kagami. Kabuto worked because of Kagami, and Decade tried to emulate that with Yusuke, but then decided to give up with the introduction of Diend and, from that point, decided bright and flashy fights and making Tsukasa look cool were more important. Monsters who were the ultimate challenge faced in the past series were cannon fodder in Decade to show off how cool he was. Characters who could curb stomp the main riders of the past were taken out en masse to show how strong Decade was.
It became less about the story of Tsukasa, his amnesia, and whether he's the world destroyer he's told he is, and more about aggrandizing him.
Add in an unsympathetic and mean-spirited character being portrayed by an actor who can't pull off "Aloof" and you have the formula for why I despise Decade, despite once enjoying him.