It's utterly bizarre to me why he says the team is "torn over what to do with the Scions." The answer is right in the game. Just look at how they were handled in the previous expansions?

ARR: Meeting and establishing the Scions, who they are and what they do.

HW: Scions scattered, forced to flee to a new city with only Alphinaud and Tataru with us giving those two time for development, get Y'shtola back a bit later. In patches we one by one (well 2 for yda and papalymo) reunite and find out what happened/what they've been up to and add Alisaie to the team.

SB: Shift focus on formerly Yda now Lyse and Alisaie as two Scions we still don't know much about to journey with, bring along Alphinaud and Tataru for support. Y'shtola is injured in the begining, Thancred is around but doing his own thing and occasionally pops back in. This gives us time to also focus on characters like Hien, Gosetsu, and Yugiri.

ShB: We reunite with our lost companions one by one, giving them each a chance to shine and find out what their time on the First has been like. We can choose which twin to visit first. Then we meet back up with Thancred and meet Ryne. Urianger gets a glow up and chance to be his own character in Il Mheg. And lastly, they all convene to find Y'shtola in Rak'tika. Each Scion got a whole zone to tell a story arc with and let them shine. G'raha and Estinien join the Scions in the patches.

EW: (should have been two expansions) Started to drop the ball a little here, but we still had some good stuff. First two zones, the Scions split up so we didn't have to try and cram them all on stage at the same time, for example. That gives room for things like introducing Erenville in Labyrinthos and having fun with Estinien as a new Scion in Thavnair. Feels like Y'shtola was about to have some character development in early patches and then nothing happens.

DT: "what do we do with the Scions??" answer: cardboard cutouts with no personalities that barely interact with the new cast. Huh???

What do you mean "what to do with the Scions"?? Do anything but the last one! Cycle them in and out of the spotlight! Have them living their own lives and doing their own thing when not in the party! This isn't difficult!