First you nerf tank supports' late game...
...Now you're nerfing mage supports' late game? And alot of them aren't even getting compensation buffs for the nerf to Spellthief's mana regen. So you're nerfing their early game too. Do you want support to be the useless-after-6 role?
I mean, it's fine if you want to make supports the earlygame-only powerhouses to match the ADC's lategame-only powerhouse status. But I thought Riot didn't like to force the meta. This looks an awful lot like forcing the meta.

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Out of the eight of them, ONE is a Tank Enchanter. And that's if you even consider a shield a buff. If you don't, then the list shrinks to