Mostly I do it like this (Basically from top to bottom, was this one in this run? if not, go one deeper):
- Was someone just a delight and maybe stuck around for a littelchat afterwards?
- Was there a player who took the time to explain mechanics to a new player or helped them out when it became clear a player had problems with a certain mechanic?
- Was someone reminding the group to wait for the new guy to watch the Cutscene?
- Did someone remind people of Food Buffs in case they were leveling?
- Did the Tank stop to ask the Healer if his pace was ok?
And if all other criteria fail, Healers get a commendation just for existing, because they decided to play the most boring job in the game just so people who dont want to can play too.