For this game, as for any others, it is, what it is. So either enjoy it for what it is or go search for another one that is more for your taste. I personally try to not interfere in the devs plan (that much). If I give some ideas, that could be used in the game, if they will be used, then I'm happy and if not, then I'm happy too.
Although I agree, that the cast is very big and as a result, we get little screen time per LI (that is purely mathematics nothing more). As other also stated the cast is unique and I haven't encountered a character that I would put under the label filler or is just here for diversity to fill the quote and please the players.