In that sense, I'm reminded of our big discussion in this thread about the mysterious identity of the 7th member of the Board. We didn't come to a consensus then..Some believed (and probably still do) that it is Cole "stuck at the end of the earth", and some are convinced that this is Astrid. Personally, I'm sticking with the Astrid option (for lack of a more realistic guess).
I was in the Cole camp, then in Astrid camp, and now I think it's someone who is yet to be introduced to the story. Both Cole and Astrid are presumed dead by the majority of people in KG, so keeping the seat of a dead person empty would be weird, whereas when Olivia asks about the that seat during the Board meeting I assumed all of the Board was 'in the know', just choosing not to disclose that info to her yet. Maybe it's one of Alexander's sisters.
As for Veronica dying in ep.10, I've stated my reasons why I believe it's possible and probable, and I stand by them. And look, I was 100% right with the identity of the 'servant' in the Red Mask, and I have that same feeling with Veronica. Narratively it's the right time to do it - you've seen her brilliance and the potential to save the world, and you'll have episodes 11-12 without her in them and you'll see the decaying world, thinking of what could've been if only she was still alive. A bit depressing, sure, but that's the point. You become a king of ashes, a king of nothing.
I'd actually prefer such an ending to 'save the world' or 'fly away in a spaceship', it's just more real I guess. No magic bullshit mcguffin to save the day, only you and the weight of your decisions, good and bad.