this question basically answers mine.
Which is better: side quests after killing the warrior or Playthrough 2?Which is better: side quests after killing the warrior or Playthrough 2?
Though it was phrased differently, and seems to be more related to leveling up a character, it was later answered with "quest rewards from side missions outside of DLC's but inside of playthrough 1 do not scale after beating the warrior, but missions in DLC's do".