I'm not sure how I feel about the 'who do you dream of...' character being pivotal or key to the blank slate PC.
More so because I first saw that character in my fourth playthrough... yeah I never used the illithid powers... only really did on my 4th run which was an absolute run. So it can very, very easily be a character you literally never see but in the character creation screen. Unless you can meet them in person at which point it would be a bit confusing probably. It's just Act 1 so early to say just how long you can avoid seeing them. I was actually confused for the longest time about what that who you dream of thing was all about considering it never triggered till I realized you need to use and abuse the illithid powers.