If you could kill off one of the scions...

[Dualblade]

Though, if I had to pick based off of what make's more plot since, I say Urainge having a falling out with Elidibus and taking that white robed bastard out in the process would be a fair ending for him. He'd get to be with Moon and Louisoix again and Avenge both of their deaths since the Ascians were the reason the two died to start with.

I actually got to go with this, with a side of "I'd rather not have more deaths/"deaths" for a bit on the good guy side. Estinien is already close enough to "we save him only for him to immediatly die because A. Nidhogg, or B. Lahabrea (STILL sure he'll be back.) Atleast here we have a good reason for it, a possibility that while things may be in partnership right now they both know it won't last (atleast if he doesn't end up a traitor, which if he is he probably isn't on their side anymore after Moen's death.)

[Kaiser-Ace]

At least here we have a good reason for it, a possibility that while things may be in partnership right now they both know it won't last (at least if he doesn't end up a traitor, which if he is he probably isn't on their side anymore after Moen's death.)

Moen's Death hit me hard in the feels too. I lost someone IRL not long before that was to me like Urainge was with Moenbryda. So I actually empathized with Uriange emotionally with that. And I gotta say, I could really see him losing his shit to take out Elidibus if he starts bad mouthing Moen as being nothing but a pawn and Uriange not giving a damn about the consequences. (End up taking him out with a forbidden offensive spell that makes Ultima look like a pop gun by comparison)