Great guide! I main Lux, she's the best.

One thing I notice about the guide is that it caters to a single situation. That is, I feel like it kind of assumes you are going to neeed the sustain from the stacked Doran's Ring and the Chalice of Harmony which later builds into Athene's Unholy Grail with the CDR and then you can keep the Sorcerer's Shoes.

Working around your build, I would suggest adding some alternative situational item choices.

Kinda like if you know you counter whoever is going mid, and won't be getting hurt very often, maybe starting with a Kage's Lucky Pick just before getting your ult up would be nice for the extra AP and gp5 to make sure you don't fall off late game.

And maybe have (bear with me) Clarity as a viable summoner spell? Just a suggestion. This would have to go along with alternative item choices. It would probably get rid of the Athene's build in exchange for more burst a little earlier on. I feel like sometimes it's hard to really get a chance to use Ignite with Lux since most of the time, you're staying back and harrassing with her E, and when you engage, you're probably planning on getting the final shot with your ult or you're going in to save a friend with the CC and won't want to get killed yourself.

Again, awesome guide! I'd love to see continued work on this. Maybe check out my Lux guide when it's finished?