To be honest, I think that the plot of the Inheritance Arc so far is quite astounding. Although the Shimon felt like they were out of nowhere at first, the way the author integrated them into the plot was quite well done. I personally would find it interesting if we ended up seeing 'Ocean' or 'Sea' Flames (Maybe the Mare Rings?) eventually, forming a Sky/Earth/Sea theme.
However, I have to agree that the pacing was horrible. Ryohei's fight was quite well done and it genuinely made Shimon seem like a dire threat. But the fights that occured afterwards slowly began dwindling and felt shorter and less overhwelming. However, I do like the plot twists that occured, such as Daemon Spade turning out to be the cause of the whole arc (It was quite a popular theory since the beginning), him wanting possession of Mukuro's body, and actually succeeding. The chapter where it turned out that Primo had saw through Daemon's plans was quite epic as well.
But back to the chapter, I think the fight is rather fitting. Hibari still hasn't settled his score with Mukuro yet, so this is a good chance for Hibari to get a shot at doing so (Although yeah, it's really Daemon in Mukuro's body). And judging from Daemon's speech, something might have occured between him and Alaude in the past. It would be interesting to see a Daemon/Alaude relationship in the past that is similar to Hibari/Mukuro's current rivalry in the present.
As for Daemon possessing the Shimon Rings, I think it makes a fair bit of sense (Since the other Shimon Members are practically helpless inside the Vendice Water Prison) and it does make for good suspense. Unlike Byakuran, whose power was rather underwhelming considering all the hype he got, Daemon might actually live up to all the hype he's worth.
Although personally, I also find Daemon possessing the Vongola Gear a bit far. Although the Shimon Rings could make sense, the Vongola Gears is a bit too much. I do hope that the Vongola Gear turns out to be an illusion, but if that doesn't happen, it's quite certain that it'll have something to do with whatever 'Flame' that Daemon had recently obtained.