I think there's still a lot of interesting stuff in this series besides Deido, but he's definitely the *most* interesting part. And it's always hype when we cut to a scene focused on him. And this looks like it'll be a straight-up battle sequence between Oujin and Deido, with Souboutei splitting its power involuntarily between the two of them. That's like, one of the most unique battle setups I've seen in manga lol.
I'm still baffled at what the hell Oujin's motivations could be. Cuz like... there has to be SOME reason he's doing all this shit. Deido and the invaders have had their motivations so fleshed out over the past 200-ish chapters, that adding a new villain who's just one dimensional and evil makes no sense. We've gotten hints about how he's been working for Souboutei since he was a kid, but there's still a very long way to get from "potentially shitty childhood" to "wants the entire world to die". It took like 5 full chapters of flashback and several long monologues to get to that point with Deido, so.... hopefully Oujin is given a similar treatment soon.
I'd theorized during the last couple Deido scenes that he would get character development through falling in love with Kurenai, and that seems to be mostly confirmed in this chapter. All this setup is gonna be so awesome in the upcoming chapters, I can feel it. Though that's not a hard prediction to make, since everything with Deido is hype lol