Consider a mana cost reduction to Lux?
A lot of Lux players are complaining about the mana issue Lux is having right now, and I personally agree that Lux's early/mid game mana cost needs to be adjusted a little bit.
She is having a hard time wave clearing in lane and farming under turret against a lot of pushing champs in game. And her mana problem is making her unforgivable to fall behind in lane. A blue buff feed is almost mandatory to keep her in lane.
Currently from level 5 to 9, her mana can only allow her to cast about 2 QWE combos in fight. Often it is not even worth it to hit the enemy champion with your whole combo in laning, because the damage is usually not sufficient to kill the enemy, and you will not have mana to cast your whole combo next fight. This really discourage Lux players to make plays in lane. Playing passive is also not that effective because her clearing problem. (2 E to clear back lines and 3 E to clear E without auto attacks, and it causes even more mana problems).
Her max level of E cost 130 mana. Lux has been famous for her mana cost back in the days when Morellonomicon and Athen has roughly twice mana regen in early/mid game, so I think it's necessary to reduce Lux's mana cost a bit in early/mid game. Reducing E's max mana cost to 110 would seem reasonable for me.