So, I'm using a pure mage, specializing in conjuration and destruction. As I find more and more enemies that are resistant to a certain element, it seems like it may be a good idea to specialize in two elemental perk trees (ie. fire and ice). This way, down the road, I will never be unable to damage a certain enemy effectively. My main concern is that doing this will use up perks that I hope to use on enchanting. Thoughts from anybody who is level 20+?