Dark Harvest vs Arcane Comet

It's just pre-nerf Aery vs inconsistent-as-ever Arcane Comet all over again. If you're playing a poke champion, the conditional aspect of DH isn't really that. Comet can be juked by walking in a straight line and the damage isn't even that different!

Dark Harvest: COOLDOWN: 45 seconds 40 − 80 (based on level) (+ 5 per Soul) (+ 25% bonus AD) (+ 15% AP)

Arcane Comet: COOLDOWN: 20 − 8 (reduced by spell-hits) 30 − 100 (based on level) (+ 35% bonus AD) (+ 20% AP)

Yes, the cooldown difference is substantial, but the payoff is greater. Arcane Comet actually scales backwards, as eventually everyone has tier-2 boots and Comet struggles to hit them. It's had this problem since its inception, as well, when everyone took Aery even after its damage was less than half of its sister keystone. I believe that Arcane Comet needs some kind of minor tweak to bring it back into the conversation. Making the missile size scale with your level or adaptive stat would be a decent start, or perhaps the missile speed itself. It just seems that if I'm playing Xerath mid, and I'm building a runepage in champ select, Dark Harvest is the clear winner over Comet.