The first thing I would like to see done is taking that "Utterance Builder" concept taken and expanded upon.
That is, in a style somewhat similar to Alpha Protocol or Mass Effect, every response to any given situation should involve a "conversation stance", where you apply some sort of body language, tone, or sheer personal "aura" of some mood or another to influence characters when you talk to them. This combines with the eventual Personality Rewrites for NPCs and the player character judgment of NPC personalities to make specific types of personalities react better or worse to different types of conversation stances.
Hence, you might get far intimidating slightly nervous people, but extremely shy people might just clam up in a total panic if you are too intimidating. You might be able to flatter proud people into saying too much or feeling more comfortable around you.
How you go about doing this, however, can lead to a sort of player "karma" for how they have acted.
In most RPGs, you are typically judged along only one or two axis of morality or personality. There is one series of RPGs (
Growlanzer) I remember playing, however, that had a much more complex system, where they gave you a flood of multiple choice responses to virtually every situation your character found himself in. You step out of a cave, and a monster knocks a boulder down, and it's rolling towards you and your party - do you (A) Scream "AAAAH! BOULDER! AAAAH" (B) Order "Everyone to the sides!" or (C) Just dodge it silently? Nothing in the plot actually changes for the decision you make at that point, but what you pick changes different aspects of your personality karma. You are judged as being either "Hotheaded" vs. "Cold", as well as "Optimistic" vs. "Pessimistic", "Sarcastic" vs. "Forthright", "Cautious" vs. "Reckless", and even has a gauge for whether you have been a ladies man and one for if you've been showing some "flamboyant" tendencies (and there are ending pairings for male characters, if you choose to go that route...)
Putting this sort of karma system into DF, however, could be as easy as simply using the personality traits that are present in all the dwarves already, and modifying them for use with Adventurers themselves. (Although some additional personality traits or invisible karma gauges might be worth adding in.) Player characters who use aggressive tactics and frequently bully the peasants into doing what they want, and act with general rashness tick their ANGER personality trait upwards in-play as they act.
The game should probably use a more sophisticated "experience" counter for ticking these personality traits upwards and downwards, however, as a single point up or down per time you act aggressively will wind up with all players quickly having extreme personalities.
If conversation stances are more nuanced than a simply "be aggressive" stance, for example, by letting you set some sort of slider or "only be 40% aggressive" meter, then this would also prevent players from going to too much of extremes. Players that leave themselves on 40% aggressive sliders will only go up to 70 on the anger meter.
PCs who flip between neutral and extreme aggressive stances or between aggressive and passive stances frequently should take more and more "experience" in being aggressive to reach the higher levels of aggression, so that your personality becomes more "fixed" over time as you play. That way, running into a few people whom aggression is particularly effective against and using it on them a few times in a row won't make a mess of a personality trend you've already clearly established.
This personality profile your character generates should be judged by the characters you meet, who will also be judging you by your actions (trying to judge your character, themselves), as well as by your reputation (if you have been building relationships with people in their village or faction, or are famous).
A cold, rational type who keeps their emotions veiled might be inherently distrusted by the warm, gregarious types, because they will suspect anyone whose emotions they can't see as being someone with something to hide. That same cold, rational type, however, might simply look down upon and disdain those who are "overly emotional" in their eyes.