We all know Ace, the guy who pretty much peaked during his debut battle against Dan, and he's also the Darkus Hero Brawler that fans seemingly feel the least amount of appreciation for, which is honestly tough, because his competition consists of Alice/Masquerade, Ren Krawler, and Spectra. I've always heard people say that Ace would've been better off if Shun wasn't on the team where he was one of the main characters.
It's honestly sad to me where his character ended up, because initially to me it felt like they actually did have ideas for him, but later, they seemingly forgot and/or didn't know how to expand on them. Not to mention, whatever defining traits his character had already existed in other, more popular characters. He's defined by his intense ego, like Dan, and he's also defined by his edge, just like Shun. And even his relationship with Mira is supposed to be a direct parallel to the one shared between Spectra and Gus. Basically, both Gus and Ace carried intense devotion for their respective fermin sibling. However, Spectra and Gus simply had way more scenes and moments dedicated to them in comparison. All in all, Ace's character was basically a redundant archetype.
In the beginning, it seemed like they wanted him to serve as Dan's main foil within the team, but then as soon as Shun was brought into the show, Dan's Main Rival and Best Friend, Ace kinda became that guy on the sidelines. Shun has always been Dan's direct contrast as a character from Battle Brawlers onwards, practically the Sasuke to his Naruto in that sense, except that they have a way healthier and believable friendship.
I honestly will admit that despite being our beloved deuteragonist of the franchise, Shun didn't have much going for him in this season, but at the same time, it's hard for me to not imagine Shun being in this season either, because he looks the coolest in the Resistance Outfit, for me at least. I feel like Ace could've somehow thrived even with Shun being in the season if they simply leaned into his need to be the "cool guy" of the team and really leaned into his parallels with Dan and Shun. Like, his exterior should have started showing cracks of frustration, because he knows he's not a "Chosen One" like Dan, or a seemingly flawless vanguard like Shun, but he should still have the desire to prove that even with the two of them on the team, he can prove that he belongs in the upper echelon of the Resistance.
What do you guys think? I'd love to hear your thoughts. I would love to go into more detail, but I think I got the topic through, and it's becoming a bit too long. So, yeah...