Making Stinger a more specific building block for AP/AS items?
Right now, Stinger is literally "that AS/CDR stick that only builds into Nashor's because RIP Zephyr and nobody cares about Dervish Blade".
So, if it's only going to build into Nashor's, and since AP on-hit based champions aren't as fond of the new Runaan's, why not patch up both problems at once?
Stinger
Recipe: Dagger (300) + Amplifying Tome (435) + 565 = 1300
+25% Attack Speed +25 Ability Power
Unique Passive: +10% Cooldown Reduction Unique Passive - Arcane Blade: Your basic attacks deal 5 (+8% AP) bonus Magic Damage on-hit.
Nashor's Tooth
Recipe: Stinger (1300) + Fiendish Codex (800) + 900 = 3000
+50% Attack Speed +80 Ability Power +20% Cooldown Reduction
Unique Passive - Arcane Blade: Your basic attacks deal 20 (+20% AP) bonus Magic Damage on-hit to units, and half that damage against structures.
Cert's Stormfront
Recipe: Stinger (1300) + Recurve Bow (1000) + 400 = 2700
+50% Attack Speed +60 Ability Power +10% Cooldown Reduction
Unique Passive - Wind's Fury: When basic attacking, bolts are fired at up to two enemies near the target, each dealing (45% AD) Physical Damage. These bolts cannot critically strike, but will apply on-hit effects.
Unique Passive - Arcane Blade: Your basic attacks deal 15 (+15% AP) bonus Magic Damage on-hit.
Probably need some cost efficiency adjusting since I hadn't bothered to math that out for this, but this is just a general idea. Basically, Stinger is now baby-Nashor's, and also gains an upgrade into a new AP-oriented Hurricane.
Just my 2 cents.