We should probably think very, VERY carefully about the kinds of nerfs and what effects they would have.
Is Teleport really so much more powerful than every other skill? Is it really the ONLY skill which is just so broken that it must be given a lot of super-special restrictions which no other skill has?
Would such restrictions apply to the Teleporter gives, or are they exempt and full-power?
Teleport is such an incredibly useful utility skill for non-combat and for exploration that I would be very hesitant to nerf it across the board and restrict it and lock it away from non-mages, even though every other magic skill is okay with just a single point in any other school. I would not want to restrict Teleport (and by extension the magical gloves) to the point where you pretty much force every single party to carry a mage specialized in air magic.
There are a ton of locations for exploration which can only be reached with the current Teleport. Break the maximum range and then there's a hefty loot difference between air-mage parties and all other parties. That's not ideal for balance.
If the real problem is combat-teleportation, increase the AP cost of Teleport to 4-5 and the cooldown to 4-5 turns.
