A good start would be to include music that only have instruments you might find in a world like Wurm. Think wind, string, drum and chamber music. Synthesizers and even pianos seem very out of place. Most of the current songs initially made me think there was a pop up add coming from some other window. When I am playing the Skyrim soundtrack over Wurm, the game feels so much more polished, heroic, and beautiful! There are currenty 2 topics that need votes on this at the voting page http://wurmonline.uservoice.com