Along with your characters' strengths, they need to have weaknesses as well. An omniscient character who can remove all obstacles in the blink of an eye is not a very interesting subject. Sure, many people might wish they could be that character, but the story will lack excitement. Don't get me wrong, I encourage you to try, but somewhere along the way said character will encounter a problem he or she can't solve with the snap of his fingers. A book, essentially, is the solving of such problems, overcoming obstacles whether they be natural, supernatural, social, or personal.
To help you with this aspect of writing, let me give you a few pointers:
1) Balance things.
If you give your character a dominance over the night, make them vulnerable to light. If your character controls fire, maybe water or ice will harm him or render his power useless. If he is long-lived, maybe a crucial wound (decapitation, stabbing in the heart) or a certain kind of metal will kill him.
Don't let your character's power be limitless. The most common way to limit it, especially for magic-wielders, is in terms of energy. If the wielder casts a large spell, it is common sense that he or she will not be able to cast another of the same magnitude until he or she recovers. Same as you or I get tired after running a mile, your characters' energy can be sapped with feats of strength, speed, or magic.
Aside from limitations of energy, your characters need other limitations for your story to be compelling and believable. Even the gods written about in Sherrilyn Kenyon's Dark Hunter and Dream Hunter series and Alicia Fields' Goddesses series are not omniscient. While some may have special abilities, they are otherwise like normal men and women.
It makes for an interesting story.
Up next: Gina Gordon dishes about her wicked thoughts in honour of her new release from Breathless Press, Wicked Ride!