This is gonna sound weird, but the big thing giving me hope for the future is seeing Calyx be really divisive.
I don't know what exactly the recipe is for a beloved villain in this game, or if there even necessarily is one (except for 'pretty, sad, male', but you can't JUST fill the cast with pretty sad men) but if I've learned anything from seeing audience responses to Emet, Fandaniel, and to a lesser degree Elidibus, it's that it's a good sign when some people are reflexively responding to your villain with 'oh god I hate this guy so much'; it means that the thing you're cooking is strong enough to get responses. I can't even trust universal adulation as much as I trust a sign like this.
Also, for fun: if I'm gonna point at a character in FFXIV and say that I think they seem autistic... well, first I have to exclude anyone from Sharlayan because that's a society that values and encourages that sort of behavior, so it's actually kinda difficult to take that lens to, say, Y'shtola. Outside of Sharlayan, I'm actually gonna say Zenos: that is ABSOLUTELY someone undiagnosed, with NO coping or masking mechanisms, and only recently figured out what a hyperfixation is. (And, comparing to Calyx: we also know Zenos isn't putting on a front, we've seen him in private, he's just Like That.)