Is there an instance of this ability appearing in blue rather than white?

i guess in azorius. detention warden?

i guess o ring did it best... so no.

yeah im probably remaking this one B)

This still has P/T.

You can't control objects in exile (only objects in the battlefield stack, and sometimes command zone, have controllers).

Also, you might make the first ability to not require that you control the target permanent. (If you meet the Academia criteria then you cannot choose to untap opponent's cards instead, or less than all of your own, then; that is a slight draw back, I suppose, which is OK and I like that idea.)

Thanks for the information!

Perhaps the ability word could require that you own three or more cards in exile rather than control?

Can you own cards in exile? I'd assume so...

I don't want to change this to be symmetrical (saying as long as you there are N or more cards in exile) because that might cause the cards you'd want to run with this (cards that exile your opponents cards rather than your own) to be totally different... that would be the same as basically fully changing the mechanic... in a roundabout way.

Yes, you can own cards in exile. All objects, regardless of what zone they are in, are owned by some player.