i think what plagues FFXV is not simplicity (most mainline titles are), is the overall weak presentation that hurts the game (awesome segments here and there, ending included, but those are the exception).
Yeah, they should improve the presentation of FFXV, and show more of how the Starscourge works, I consider that one of my main priorities as well. I also enjoyed the Starscourge and what it did to FFXV's world, and I enjoyed fighting Daemons, I would like to learn more about it at some point, even if they re-do the Revelation of Bahamut to go into detail about it. But that's just my opinion. My best moments with FFXV were so far, were meeting Ardyn in various chapters, Ramuh's trial in Chapter 5, the encounter with Ravus in Chapter 5, fighting alongside Aranea in Chapter 7, Ardyn's mind-games in Chapter 11, Ifrit's back story alongside the Great War Of Old in the re-worked version of Chapter 12 that update 1.16 brought upon, Chapter 13 where Ardyn revealed his identity, and the Revelation of Bahamut, and Chapter 14, in the World Of Ruin, along with the state it was in, I can't wait for Comrades to get into the World Of Ruin in it's first integral phase right after Chapter 13's events, and the fights with Ifrit and Ardyn, and Noctis' sacrifice.
Edit.:
Here's something interesting, near the end of this video, this person managed to hack the game, and found that Ardyn was shown as a Guest character, along with a model on the character menu.: