Yeah you should really animate it, even something simple would be good

Some kind of pulsating explosion in the middle or something of that nature

That would be easy to animate!

 Nice :)

I'd suggest using the darker yellows rather than black in the dithered glow closer to the blades.

 Aha, thanks! I updated it to fix it.

 I just had another look, at videos and the like, and they're always yellow or white. No matter what physics may say ;D

[/nerd]

(A mixed glow, however, would be purple :P )

 Red + Green = Yellow

so

Red + Blue = Purple?

Not really sure myself, but thats what I figured at least.

 I thought lightsabers made yellow when they touched :P