My feeling is that it will be more important for the story, it's adding some kind of relationship meter for your character like mass effect, and certain level of trust may lead to that particular character cutscene or setpieces. Adding that system to the squad command is just to make the system more cohesive, more tied together, so you can see the trust in gameplay.
I think it have potential, imagine scenario where character with low trust level betray you in the middle of the game and become enemy, while the alternate scenario with high trust level is he actually push you out of harms way and got killed saving you. Both scenario lead to that member leaving your party, but give very different emotional impact.
Managing your tezm trust will become the metagame, try to beat the game with all member having high trust level, since you can only bring 2 other ai member at a time, you're choosing which one to prioritize etc.