Truth to be told...
I didnt even know he had such a thing nor many people can even see the marker properly, even less if:
-In team fights
-Auras, or other on-champion effects (like Nasus' ult) covering the marker
-Colorblind people will probably never notice this
Unlike Cho's execution markers, many other champ's markers are above head: Garen's villian, Evelynn's X, Pyke's red HP bars...
Left: Really... a pulsating aura-lookalike I didn't even know it was meant for Cho'gath
Center: Like give him something for what he represents like a maw surrounding the enemy champion ready to be eaten whole
Right: I actually like this one