A small buff regarding Lux
Make all her spells be able to detonate the passive applied by another spell (similar to how her R already detonates the passive applied by either Q or E).
Right now, she needs to Q > AA > E > R > AA in order to achieve maximum damage, which NO ONE ever does because it's counterintuitive to walk in range of enemy just to proc passive in between her spells. Not to mention, the snare will wear off before she can cast her ult.
She's one of the few champions who cannot fully utilize their passive, which is why all Lux players only bother doing QER + Flash AA to get the last slither of health. I know she's already in pretty good standing right now but since Riot wants to make her relevant for pro play, I think this would be a good direction to take as its not a flat damage buff