In talking about how you'd love to do it as a DM you're also highlighting an additional design failure - Everyone else just stands there and watches you feed your head to the Illithid and does absolutely nothing, and there are no options or prompts for them to do anything, in any way.
You do know you can switch to another character in your party and then smash the Illithids head in right? And you can do it during a conversation. In a sense you are complaining that you didn't do anything to intercede. You should have a word with yourself about that when you get a moment. ;D
In multiplayer I have had other players roll up to me when I was talking to the Mindflayer and kill it - "Why you talkin' to that? You knows its an A-hole!" -Actual Quote
I don't know how I feel about the entire encounter on principle and you both make pretty good arguments, though I think I lean a bit more towards Niara's side, especially regarding the requirement of multiple checks. But I will also point out that "you can control your companions even during conversations" is not an excuse here. Firstly, the game never really tells you that you can do that, and it is such an unusual game mechanic in crpgs that I wouldn't be surprised if most players don't figure it out until long after that encounter, I certainly didn't. Furthermore, your companions are still characters that should have some degree of reaction to what you as the player are doing. You shouldn't expect them to just stand around and watch you feed yourself to the mindflayer. They should have some sort of reaction because they are right there.
