I'm still 100% positive Ven is not Strelitzia's murderer. It just doesn't make sense. Even with the new Re:Mind stuff, they reaffirmed that Ven is much too pure, even for his own good. I don't think "Darkness" has anything to do with Ven, as in, I don't think he possessed Ven and killed Strelitzia or has ever made Ven do something he didn't want to do.
I think Ven is "Darkness"'s vessel in the loosest terms possible. If the machine is the arc in the future, then Ven is the arc Darkness uses to reach it.
As for Vanitas, I'm positive that Vanitas is actually a combination of Ven's darkness (the little he had) and whoever "Darkness" is with Sora's influence coated on the very top of it all. It's why his back and forth statements on who he is and who he isn't are literally contradictory.
One moment he says his home is in Ven and he'll disappear if he goes back. In the other, he says he and Ven are not the same and have never been. So the only conclusion I can draw from that is Vanitas is MOSTLY Ven, but a little bit of "Darkness" too. I don't think Vanitas has ever acted on the whims of "Darkness" and I think Vanitas only has a surface level understanding/knowledge that he is more than just Ventus.
At the end of the day (his death), he seems to accept he will always be a part of Ven and Sora (their shadow).
"Darkness", on the other hand, seems to have a much bigger role to play than Vanitas ever has and I hope it stays that way. I do like Vanitas as an antagonist for our heroes, but I also prefer it stay... personal. If that makes any sense.
Been discussing these updates with a pal and I randomly threw out there that baldynort found amnesiac Ven in one of these pods, somehow knew "Darkness" hitched a ride in him, told Ven he was an orphan and he'd be looking out for him but in reality, Xehanort was trying to get "Darkness" to come out but soon realized Ven couldn't do it. Cause it's not Ven's darkness, but literally someone else in there.
Switching topics again. I might be misremembering, but when Ava told Strelitzia to be a new leader, that ALSO wasn't on the hill, was it? She was in town and Ava called out to her and gave her the book. Right? Neither Ven or Strelitzia met Ava on the hill?
Edit: She didn't.