Darius buffs went in wrong direction
Pure numbers isn't the best way to make him viable on high elo/lcs arena. First of all I think in terms of raw power he's balanced right now. The problem is when Darius being completely outclassed by other mechanics but stat checking people to death.
He loses against
- Split pushing
- Ranged team comps (Actually the least problem)
- Revive/heal-shielding team comps
- Simply strong all in late game champions
(She can use ultimate, remember) 
(She also split pushing type)
His #1 problem isn't even kiting part. It takes you too long to stack your damn passive so by the time you achieve that you probably would have below 50% HP and your backline will be already dead. Its a fact. He has nothing to protect his backline allies or at least provide something useful for team. You can't simply rely (as a team) on his ability to clean up fights since it actually has too much counter play.
So by this buff you make another step to make him more cheesy and still useless in terms of strategic/global gameplay. You really need to reconsider his role as exclusively clean up fighter. You may reduce his all in power but keep his ability to do fancy chain resets. I honestly think he needs utility. I don't know what kind of utility he needs: CC/siege power by giving him huge damage burst on structures or monsters/shields-heals (lol). Think about it.
As an old Darius player Im happy you want him to be popular in high elo (I remember him being trash since 3.03 nerf to brief s5 rework and then until patch 8.11) but this is clearly wrong way.
