Honestly, my only issue with all of the Preseason changes is a simple one.
Sorcery no longer grants CDR which means you can't do 10% CDR starts without investing more heavily in CDR Runes.
What really annoys me though is that the opposite equivalent, Fury, still grants V/W//X/Y/Z% Attack Speed WHICH MEANS Riot doesn't acknowledge that CDR is a Mage/Caster's equivalent of Attack Speed.
Everything else I can live with, but this change wasn't even one that I noticed until it became live and it's just a thorn in my side because it means I either have to be content with discarding my 5% CDR Rune page, being stuck with only 5% CDR from my Runes, or sacrificing other stats for 5% CDR via additional rune changes or the 'Cunning' Mastery Tree.
/
, and you typically get blue buff.
also gives you 10% CDR now.