Vi Changes are almost good. Please Buff > Adjust. Right now they're hurting her adaptability.

TL;DR - Riot is trying to pigeon-hole players into running specific runes, maxing abilities in a specific order, and building specific items.

Blast Shield (Passive) Cooldown changed from [12 - 8] to [12] Shield size changed from [10% max health] to [15% max health] [New] "Shield CD is reduced by 3 seconds whenever you proc Denting Blows.

This change essentially means that if you don't want your shield up-time to be objectively worse, you need to pull extra attack speed out of your ass. How? Well you're effectively forced to either change your itemization (building Bloodrazor instead of Warrior) or start running 'Hail of Blades'. Admittedly, Vi has been enjoying the recent buffs to the keystone, but Electrocute still has its place and shouldn't feel punishing to run.

Vault Breaker (Q) Damage changed from [110/160/210/260/310 (+160% Bonus AD)] to [20/60/100/140/180 (+140% Total AD)] [Removed] No longer deals reduced damage to minions and monsters.

This isn't a big deal. Still max it first - you only lose ~4 Damage at 6 items and we always maxed this first for the lower cooldown anyway.

Denting Blows (W) attack speed changed from 30/35/40/45/50% to 20/30/40/50/60%

This is Riot's second offence. You're now forced to put at least 1 extra point in the ability to break-even with the current version of the ability. Additionally, you're obligated to max this second if you don't want to alter your Runes or Itemization to make up for the changes to Blast Shield's up-time.

Excessive Force (E) Buffed the follow up attack after hitting with E to better scale with attack speed." AD ratio lowered from [115% Total AD] to [110% Total AD] AP ratio increased from 70% to 90% > [New] AoE can now crit

Why does this ability have an AP ratio at all and why does the AoE now crit? Nobody is running Crit Items on Vi. Not so much as a Phantom Dancer. Nobody is running Rageblade on her either to make use of the AP Ratio. Remove the AP ratio and remove the AoE Crit and put that power somewhere else in her kit.

At the end of the day, Vi hasn't seen competitive play since 2014(?) and hasn't been strong in SoloQ since around that time as well. She needs buffs, not adjustments. To use the concept of a 'power budget' for a moment, most Junglers and most Diver champions that Vi have to compete with at the moment have $500. Vi probably has $400-450. She needs Riot to give her $50, not shuffle around the $400-450 that she already has. Maybe put Vi's Passive on a static 10 second Cooldown to split the difference between PBE and Live. Maybe you don't force her to put an extra point into W that players wouldn't otherwise want to do depending on the situation.

These are decent changes, but they need to be objective buffs, not adjustments.