I think Lana and/or Theron being a traitor would get a pretty big reaction even from people who don't romance or like them simply because they're so visible/important to the plot (well, Lana is. Theron, less so). They might be the only characters that would realistically have a meaningful impact, actually. But they haven't really set it up well (I think they could both be traitors to an Outlander they have disagreements with but that hasn't really been shown in-game) and I still don't think it'll be anything more than the Scions (or other secondary characters) working for someone else.

Elara, Andronikos and Kira for me.

She has a conversation and mission after the final (well, "final") confrontation with Vitiate where she mentions till hearing him and then you encounter those other Children that still hear him too. So there was still that story hook. I suspect we won't see her for some time, though, since I think the Force-sensitive love interest companions will get lumped into a story arc together. I do agree that Scourge is the far bigger omission, to the point of me wondering where they might take him now that his reason for even being a companion in the first place is gone, especially since they dropped the ball with him in SoR too (using the excuse of "well if we had Scourge react to Revan then people would complain about the JK getting extra attention).. Given the way some other companions have been written/treated, I definitely have concerns about how well Scourge's eventual reappearance will be handled (as well as how his current absence will be explained).

Satele shows up in the post-KOTET cutscene helping to rebuild Coruscant alongside Malcom. That doesn't disprove the idea she's a traitor, but I don't really think they'd have included her in that scene if she was.

Balmorra. Definitely feels like a warzone, and both factions have interesting and unique takes on that type of story given the different roles they play.

I gave up waiting for my favorite companions, so I started bringing them all back with the terminal, story be damned. If I'm going to run around grinding heroics on my agent (or whatever character), I'd rather do it with the companions I like.

And even if they do appear in the game they don't always get much attention, like many of the characters from the trailers. Or they end up like Jace Malcom who gets his first major appearance only for it to be...well what we got on Iokath. The failure to include Kira or (especially) Scourge in Vitiate/Valkorion's story still baffles me. Maybe Bioware really did think they could extend the story long enough to introduce one or both of them, but still...

Did any heralds ever promise to support you? That would be why the Scions would be traitors, even if most people probably wouldn't care about their treason.

They haven't said anything about Khem Val and the inclusion of the discount/replacement version of him has me worried we may not see him for a long time (if at all). I wish they would bring him back in an inquisitor-only mission if they don't want to deal with figuring out how to include him otherwise. I can live without having every possible companion on every character.

I'm at the stage that several other people have mentioned - I'll recommend people try out the class stories, at least, but I'm careful about anything beyond that.

Oh I agree. But there aren't many characters that are guaranteed to be around at this point (i.e. can't be dead/gone/not recruited) and would have any kind of impact. I don't think it's Lana or Theron (too important to Bioware/the writers), Gault would have no impact and has no real motive and T7 doesn't make sense. You could go with an alliance advisor but they have no real story involvement and nobody would really care. I've seen Satele mentioned and while it's possible I guess I don't see a good angle for it, especially since (1) she's never really been a part of or involved in the Alliance and (2) she's one of the few recognizable figures in the Republic left, especially if Malcom is dead. Although that may also be partly due to me hoping she gets better writing/a better role than that. So I'm going with the Scions - they (sorta) pledge themselves to you in KOTFE and predicted you'd take the throne and now show up out of the blue on Iokath. Given how little story content there is on Iokath, I think it's pretty interesting Bioware chose to include them.

Yes, I meant the more established Jedi and Sith orders. They've been basically MIA other than Satele, Acina (who may now be dead) and a mention of Vowrawn in a mail if you sided with the Empire and decided to start surveillance. I'm guessing we'll see Force-sensitive companions return when they become more prominent. They've mentioned future returning companions will react to your choice on Iokath - mentioning Iresso by name - so I'm thinking the next pairing will be Iresso and someone like Temple or maybe Vector and then we might see things open up a bit more and maybe involve the Force users...although I wouldn't be surprised to see them give us "two for one" and cram like Ashara and Nadia or Kira or something into one update. They may get some lines (although probably more so only if you've romanced them) but their story is done at this point...even Elara's situation isn't necessarily simple as a trooper that sides with the Republic but made certain DS choices will have her refuse to join them (romanced or not). Given all that, their stories are almost certainly done, but I do hope Bioware makes up for the fact they were given almost no screen time (almost literally no screen time if you aren't a trooper/sith warrior!) and you weren't allowed to use them during the actual story.

I bet it'll be the Scions (or at least a faction within them)

I'm guessing we'll see the Force sensitive companions coming back around the same time (when the Sith/Jedi have more of a role in the story)

His letter only changes depending on whether Vette is alive or not - whether you romanced her or not doesn't matter. "Speaking of which, I was sorry to hear of Vette's untimely passing. The two of us rarely saw eye to eye, but I always respected her role in your rise to prominence. She will be missed." vs. "Speaking of which, I ran into Vette while making my rounds. She's her usual colorful self. As much as I love her friendly ribbing, I think I'll station myself far from her quarters."