Different fonts for special occasions
Case in point: Vampire the Masquerade: Bloodlines.
We're still thinking about the decision making in dialogs and we're going to try different approaches, but this is indeed something we had in mind. Using the different primary stats to act as a bonus on the decision roll, and you choose which stat bonus by choosing the corresponding option (as you said, e.g. get a bonus from STR if you choose an intimidating option).