I've been thinking alot about that area youve circled, not the signature lights, but the little indents in the bumper. Something small, like a 6x1.5" light bar would fit there. It would take some significant fab skills. I'm still rolling the execution around but IF i decide to give it a shot, I'd go with something like one of these:
or even better, some of these:
My bumper is different than yours though, since mine is a Ti and yours is a Sport. The spaces appear to be pretty close to the same size, but impossible to know for sure without a direct comparison. I've been thinking of doing either those small gaps on the front sides of the bumper or the long thin strip in the center. Haven't decided yet.