plenty enough talk on what her intentions might be but, from what I'm seeing, the actual effect so far is that keeping the 3 parties separate makes each of them reconcile with their past and current situation.
Dion has [....]
Though, all these points are sans any revelations about investigations that may come in the coming chapters.
Ya'see, that's a lot of analysis given the information we already have, or that we have to dig into. It's the writer's job to not present such a simple conflict, and have the easiest, low-hanging-fruit conclusion be: "That's stupid."
If a character has critical information, and she refuses to share it -- you better damn at least establish that the character knows more than the rest, something else is stopping her, etc. Anything.
But if the character is being an asshole about it?
Personally, I don't think that's good writing. It's like saying: "The kidnapper went to the left", and then having the chasing soldiers wonder where the kidnapper went, and they end up going right. That's no good. It's too easy to go: "that's stupid" and be angry about it.
I think a writer should, for the very least, try to prevent the audience from wagging their fingers at w/e they're writing and calling "stupid".
(And with the chase example -- the easiest solution is to just not show / narrate where the kidnapper went. If the soldiers are confused, so should the reader. This is some basic shit that I see A LOT of times in manga. I stopped reading Gantz because of it, I shit you not. Well, not specifically because of it, Gantz as a whole is pretty impressive, but also, just, really dumb...That part just broke me.)