I actually considered that - at one point I had two sheets of paper filled with equations! Instead I said screw it and adjusted the personality stat so that the first personality option you ever pick decided your personality for you until the following chapter.
First choice: %+50
Consecutive choices: %+5
(Prior to character creation, you begin with zero on all personalities. I like to think of it as a blank slate in more ways than one.)
And afterwards it’s mostly some finangling to ensure it’s impossible to not have a dominant statistic. I haven’t run through it yet as a player, but I think it should work. I believe this method was used in Bioware’s Dragon Age 2. Their wiki explains it better than I can.
If your first pick is a Diplomatic option, for example, Hawke’s voice will adopt the Diplomatic tone. As you keep choosing similar options at the dialogue wheel, they “stack”. If you were to decide to change your personality later on, it would take more than twice the amount of (either Humorous or Aggressive) dialogue lines to activate that version of Hawke’s voice. The idea behind this system is to ensure a consistency in Hawke’s delivery throughout each Act. After a certain number of specific dialogue choices, Hawke’s personality is effectively crystallized.
The issue with having “balanced” personalities in this particular game is that flavour text and such are determined by your personality. Having both diplomatic and aggressive statistics equal would result in not only rather schizophrenic dialogue, but would almost quadruple the amount of text I would have to write. Admittedly, the more immersive option would be to do it your way, but considering it is my first Choicescript game I’m trying not to bite off more than I can chew.
I hope my English isn’t too mangled to explain this!