So I started these reminders a while ago, but I gave up because there was no way for the game to check if the target was illuminated.
Until I realized Kai'Sa has this exact mechanic if her Auto will proc her passive's execute. Which means Riot does have the tech.
There's actual precedence here!
Getting right to it;
Lux should use her Crit animation when autoing targets marked with her passive, illumination.
For those of you who don't know her crit animation is her twirling her wand, it's just about never used, despite this she has a quote about twirling her wand which she almost never does.
Video of her crit.(and almost all other base skin crits if you're interested)
To further emphasize why this should happen please look at these pieces of evidence;
As you can see, this is a picture of Lux. While Lux is cute on her own, the staff next to her is simply boring.
In order to solve this problem,
As can be observed, this is instead awesome and fun. With a spinning light wand and lux's odd sparkles that were caused by me being bad with PNG files and transparency yet lend support to my cause.