Let's put CDR in utility AP items, new and old ones.

Riot has stated they might prefer to have mages choose between fewer, damage oriented abilities and a swarm of abilities with more focus on utility, rather than just always reaching the cap lategame. So why not making this distinction even clearer through items? Rylai could lose 20 AP and gain 10% CDR. You pick Rylai to lock down your enemies and get bulkier, not to scale hard. Void staff could cost more and grant more AP. Luden's could have 20 less AP, 10% CDR, more MS and you'd get this to go "hit and run". Lich bane could get 10 more AP. Morello could have 10 less AP and grant GW below 50% HP instead of 40%. 5% more CDR on Frost Queen's clam. Lucidity boots could reduce by 10% the cooldown of an ability when it hits an enemy champion.

It'd also be nice to have a few new items.