Here is my suggestions for some minor alterations to the HUD icons. Mostly it involves changing the lock icons to something a bit more helpful so you can tell locked resources from locked champions and locked quests. I also suggest changing the enemy champion icon from the same as a monster lair to the champion icon, but in the same color as the monster lairs. Also, captured monster lairs that you can build on should be changed to the monster icon, but made the same color as resources, signifying that you can build there. Maybe they could make different resource icons for the different types of resources so you could see what was what at a glance.
Here is a mockup of a screen with the different icons.