I don't know. Is a little barebones, but I reallly find this approach
interesting. I strive a lot to make adventures not based on combat only, and characters to spend their resources on the Exploration pillar. I acknowledge that I'm not great building social interaction scenes according to any systematic principle, as I don't have a particular guideline to make this pillar a real
challenge, but at least I don't suck, because of the Angry GM
Systematic InterACTION! rules.
About experience alone, this is
great, at least for D&D standards. The XP grind was always cumbersome and counter-intuitive. I don't really get why they use such pointless XP tresholds at all for advancing levels (unpredictability, perhaps?), and this numbers are much easier, and they really benefit the other parts of the game meaningful for character advancement.
Nevertheless, the main "but..." is that there are no real guidelines to make "harder" social encounters, and very little for Exploration challenges, that can be easily done by a level 1 character. The significance of the NPC is useful, but it doesn't escalate as well as the monsters combat abilities. There are loose guidelines in the DMG for both pillars, but there are nowhere near as detailed, polished or engaging as the Combat engine. Maybe stablishing certain difficulty tresholds for certain challenges?
EG:
Local knight: Diplomacy (Persuasion, Deception and Intimidation) DC 10-15. Doesn't require any particular trait to be acknowledge by him.
Baronet: Diplomacy (Persuasion, Deception and Intimidation) DC 15. Requires Nobility trait or the introduction by a knight.
Duke/Baron: Diplomacy (Persuasion, Deception and Intimidation) DC 15 to 20. Requires Nobility trait or the introduction by a baronet or minor noblemen. Also, requires some form of renown and influence. He can grant the Nobility trait (knightship).
King: Diplomacy (Persuasion, Deception and Intimidation) DC 20 to 25. Requires a high Nobility trait or the introduction by a trusty counselor or high noble. To know the king and ask for a favor is only prerrogative of a few, but a king may want to know any high renown folk, such as a hero.
Emperor: Diplomacy (Persuasion, Deception and Intimidation) DC 25. Only a few can claim to know emperors and whisper in their ears. Only the most powerful nobles and kings can grant an audience with an emperor. Only great heroes or villains may be known enough for an Emperor to hear of.
Demigod: Diplomacy (Persuasion, Deception and Intimidation) DC 30. Only the greatest heroes can claim to attract the attention of the divine.
Having renown on a faction may be the threshold to attract attention of an importan figure, such as a duke or king.