1. Do you see any way to reward players for actions that are more difficult to measure (behaviour, leadership, social interaction etc.) and not necessarily related to combat or traditional level progression?
Well for subjective things like that, the only thing I can think of right now is some kind of reputation system.
2. If a player (for any reason) was to be rewarded, in-game or out of game, what kind of reward(s) would you consider appropriate?
In-game I would say things that look cool but don't give an advantage in gameplay. Things like an awesome weapon or armor skin, an emote, or a title.
Out of game, it would be hard to go wrong with Aion swag and/or cash
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