How to properly reapply CDR to items

It's getting tedious to itemize CDR in the current game. If you're a manaless AP, it's nearly impossible in same cases to achieve 20%+ naturally. For instance, Zac used to achieve 35% CDR naturally, and now you strain to get 10% voiding runes (which you shouldn't be forced to use).

Begin with the jungle items Riot has skewed, and integrate into other items. A possibility is adding 10% to Sunfire Cape, seeing as it's forcibly niche now, being used exclusively by tank spell casters that build no other damage. Cut Runic Echoes MS in half, but grant it 10% CDR. Then simply slap 10% CDR on Cinderhulk or rework it into an actual tank item with CDR on it.