I would love for their to be DAO-style Origins for BG3. Alas, it is probably too late for Larian to start working on them. It'd be a bogglingly-vast amount of work considering all the race-background-class combinations.
@Niara has, at various times, suggested an interesting way of introducing backgrounds and personalities. My explanation certainly won't do it justice, but I'll attempt it. After the tadpole-insertion scene, there is a dream scene where the tadpole is trying to get to know you (to better control you I guess?). They ask various fairly vague questions about your history, what drives you, your personality, etc. Your answers help define your Tav, adding personality/history tags. Later in the game, things can differ depending on what you answered, you could get some quests related to your answers, etc.
