The main use for this zone is farming materials for devil's weapons. Current rates are pretty low and the XP is some of the worst in the game.
Suggestions:
-Increase exp from these mobs 100-150% (will still be very low xp/hr)
-Add completed devil weapons to the mob loot tables (0.01 or 0.02% chance)
-Add kill quests for devil shackles or the ancient magics books