I am veteran MMO player, and I have never seen instance runs yield so little xp.
This should have the devs concerned because it discourages play of one of the most fun and social aspects of pve in this game - grouping to run instances.
Other than a chance at winning a blue item - that most who run the instances probably don't care much about - running an instance more than once is a net xp loss from completing quests.
Devs you need to at least make leveling through dungeons (and pvp for that matter) on par with simple quest completion for xp. It is becoming more and more difficult to find or make groups to complete group content as players become aware of how little they will advance by doing them.