Sigh, here i go again.
I say buff all three to the point where Supports no longer lag behind in gold compared to the team, make every one of them unusable by other laners/junglers, and then raise the cost and item power of every support item in the game to be around 2600 to 3400 gold (Including these and Sightstone.).
Yes it would break the game for a whole month or so, until people got used to having 5 people per team instead of 4.5 people.
And when i say make them unusable by other laners, i mean keep Spellthief and Frostfang's restriction (and strengthen it and also make it apply to monsters.) on Frost Queen's, i mean code the Relic Shield line cut champion's damage to minions by half outside of the execute proc, I mean make Coin's line stop dropping coins when you kill minions and monsters, similarly to Spellthief's line. Hard restrictions that will block abuses, that if laners do take these items, they can no longer gain from minions and keep their income stable with the item instead.
When i talk support item buffs, i'm saying shove an extra 40 AP and on Ardent Censer and make the damage buff scale with player's AP (Like 5%), Buff the Magic Resist and AP per Mana Regen on Athene's. Give Mikael's Crucible actually useable stats, preferably for tank Supports. Give Sightstone some MR and Armor. Give Eye variants more stats in general. Give Frost Queen's Claim more damage on proc, or make it have an AP scaling, the Talisman of Ascension Magic Resist to match it's Armor, and so on, and so on. These would all be 400-1000 gold costlier, take longer to build but allow the support to have an impact that evens to that of the carries all the way to the late game.
Also, don't tell me other champions would abuse. Tanks will be tanks regardless where they go, if Mikael's or Sightstone happens to be slot efficient for them, i don't see the problem.
For AP mages abusing this? I don't think Ahri, Akali or Brand would have ease proccing Censer or Athene's with any kind of efficiency in comparison to Janna, Sona and Bard, regardless of the item's potential. They'd still go for their still superior burst damage items. The main difference between AP mages and AP supports' builds would simply almost entirely rest on the item's passives.
*Also, for your question, i say buff FQC and FoTM income, obviously.
are busted and generate too much gold, or 
and 
are garbage and don't generate enough gold.
