Jumping in here. I REALLY wish there was some way to prioritize interactions with the companions you want. I find despite being "high" attitude with Astarion and only medium with Shadowheart and neutral with Lae'zel, the game still prioritizes their interactions. I literally have to knock both of them out before any of the Illithid dream sequences if I want to get the Astarion interactions. Don't get me wrong. I love Shadowheart and plan on romancing her, just not with that particular character. But I find I need to use her or Lae'zel a lot because otherwise my party is just too squishy. *sighs* Please, please, please allow us to have some way to prioritize interactions with the characters we want.
