Maybe it's just me, but whenever there's a "special" option, I feel pressured to use it. Because it's special, clearly its the best. Maybe that's why I flirt with everyone...
So, if the point of companions interjecting is just to give an opinion, I'd kind of like them to just speak up on their own, like they did in DA:O. Or to have a general "anyone have an opinion?" option that doesn't feel so special to call out specific people.
If the point is for them to try and get something done - like say, Cassandra intimidating someone into doing something, well first off: I think part of why they did that in DA2 was because the player didn't have Intimidate or Persuade options, and I really hope DA:I does. I would much rather do the intimidating/persuading myself than asking companions to do it. Secondly, I would like for them to not always succeed at getting something done - that way it's a gamble, just like any of your own actions are, and not just a "special companion option = win" thing.