Bringing back Ava Jaxo I also support. I wish we could have gotten her as a trooper companion. The only problem is that the only way she would return is if you saved her. Her return would be based on the indiviual players choices.
Exactly. Characters that live or die by player choices (such as
have a sort of a Schrodinger's Cat existence -- in the wider context of the game, their "alive-ness" is indeterminate. So, the only thing BioWare can do (without really stretching plausibility to the breaking point) is to make sure you never see them in the game again.
It's events like these that show how illusory our choices within the story are).
As for the original idea, at least on 2 of the Storylines -- the Consular and the Trooper, you do temporarily "lose" a companion, due to events in Chapter 3 or the end of Chapter 2.