Kinda tangental, but I think Sunburst has some of the most interesting development. He was only really in like one episode, but we learned about how he was so ashamed to Starlight about his failures in spite of his expectations, which came off as very relatable. A combination of depth and relatability made him perhaps my single favorite male character in the show.
Spike’s tough competition, though. But much of his charm just comes from his age. Though I like how straight-man he can be sometimes.