Mini-Changes to Lux
Maybe some players will find these more drastic of a change, but it keeps her core gameplay and identity in play as in if R is up then you land your root and annihilate your opponent.
What the idea will propose is this: Take away her no-counter-play instant E burst poke damage and in exchange grant it heat up power, with adjustments to make this work, which makes her E actually synergize with her snare. In turn the improvements will be a greater reward system for landing your root with your E, and better waveclear (actually can one shot the back line minions all the time [obviously with AP]), in exchange for less easy poke damage / doing the easy poke damage Es means a lot less damage Es if you don't let the E hit up over time - E still slows.
I also want to do some other changes, like reduce the damage of her passive but make it proc on all of her abilities and just ultimate and attacks, even though it may be a numerical damage drop the passive damage goes up because of the efficiency. Also some kind of change to her shield, a quality of life function that doesn't return it to being oppressive.
Illumination (Passive): Lux's offensive abilities mark struck enemies with light energy for 3 seconds causing Lux's next basic attack or offensive ability to detonate the mark and deal 10-100(+20%AP) bonus magic damage. Final Spark will detonate and re-apply a mark of light energy.
Light Binding (Q): Cooldown: 15/14/13/12/11 seconds; Cost: 60 Mana; Range: 1175 units Lux releases a sphere of light in the target direction dealing 80/110/140/170/200(+60%AP) magic damage and binding for 2 seconds against the first two enemies struck.
Prismatic Barrier (W): 14/13/12/11/10 seconds; Cost: 60 Mana; Range: 1075 units Lux shields herself and struck allied champions in the target direction and on the return shielding for 40/55/70/85/100(+20%AP) for 3 seconds for each pass which can stack on top of each other.
If the projectile passes through Lucent Singularity then the shield strength doubles against struck allied champions and Lux.
Lucent Singularity (E): Cooldown: 7 seconds; Cost: 80/90/100/110/120 Mana; Range: 1100 / 350 units Lux sends an anomaly of twisted light to the target location for the next 2 seconds slowing enemies within the area by 50/60/70/80/90% that decays over the duration.
This twisted light heats up over its duration dealing between 30/40/50/60/70(+25%AP) to 120/160/200/240/280(+100%AP) magic damage.
Lux can detonate Lucent Singularity early by casting this ability again.
Final Spark (R): I'm lazy, so just going to say this is the same ability. This ultimate is in a pretty decent spot already; possibly can afford to nerf the cooldown later on with a change like this new Lucent Singularity works out since that would greatly help with Lux's wave clear issues which makes Lux's threatening moments (especially early game) less frequent with the super high damage beam ultimate becoming less frequent.
So more balancing options you can take by delaying E's damage and having it better for waveclear and removing Lux needing her ultimate to waveclear. Also this E just makes better sense with her kit, the slow being stronger but decaying as the damage heats up helps Lux land her snare and the snare sets up her target to take the fully heated up duration E damage and is hard to get off max damage with the slow decaying over the duration, but easy and rewarded for landing your abilities and using them together. Damage I shifted from her snare to her E as well, really tried to tone back Lux's easy poke damage, in exchange for a bigger reward for landing skill shots and setting up your abilities with your other abilities.