[quote=@Draku69]
What about a variation of lightning? Like black lightning?
[/quote]

I think the issue is that they don't want duplications of abilities so it washes out the "uniqueness" of characters. And a black lightning variation wouldnt actual change the application of the magic, only it's color. 

If you would like we can brain storm ideas outside of the major elements that might interest you if you're only interested in lightning, elementally speaking.

Like you could use Light Manipulation. Able to harness and manipulate light waves, amplify them or simply bend them around yourself or objects creating a degree of invisibility.

Or Organic Manipulation. Able to controller organic materials like Flora and trees, etc. Sort of like a "Poison Ivy" from DC Comics.

Or Kinetic Influence. Able to manipulate the kinetic force of an object. Either amplifying or diminishing an object kinetic force. Like "Gambit" from Marvel Comics.

If not of those interest you let me know what kind of things peak your interest and I can brain storm some more stuff.