CDR cap and changing support itemization

Patch 4.10 has two big changes to support itemization, the addition of Ardent Censor and the upscaling of Mikael's Crucible. Both of these items have 10% cdr with the upcoming patch which is nice for individual items but increasingly looks cost inefficient as I try to work the changes in to my existing builds.

The problem is that cdr is perhaps too abundant on support items, aura items, and common support ap items.

Most supports will take a gold generator. This gives 10% cdr for Frost Queen's Claim and Face of the Mountain or 20% for Talisman of ascension. In addition many of the supports such as Lulu, Nami, or Sona will want a mana generator because their spells cost a lot. The options for that are Mikaels (10%), Athene's Unholy Grail (20%), or Morellonomicon (20%).

At this point if I went the Talisman route I am probably already sitting on 30% cdr. Or if I opted for the Frost Queen's and one of the ap mana generators. Its hard to tell without having played with it yet but Ardent Censor looks like a strong choice for champions who can use it, Nami, Sona, Janna, Lulu, and Soraka. This will bring these champs up to 40% cdr in some combinations. Ok, that's great but if I'm already at 40% when I have 5 items (assuming Sightstone and boots) what do I build for that last item that still brings some utility to my team?

On the offensive side Banner of Command and Zeke's Herald both have 20% cdr. Twin Shadows has 10%. Defensively Frozen Heart and Locket of the Iron Solari have 20% and 10% cdr respectively.

There are a few items that have utility and don't give cdr. Ohmwrecker and Rylai's Crystal Scepter but neither is particularly appealing except in niche cases.

Ultimately, while supports may not be going over the CDR cap in every game or even most games, there will be some games where they pay for stats that they can't use because most utility itemization features cdr and it feels like crap to pay for stats you don't need even if the item is what the game calls for.