In my current playthrough I've just slapped Teleport onto Ifan my Rogue because he's pretty inept at being a Rogue and he needs something to do with his AP when he can't do anything else.
What is "willpower"? There is no such thing in D:OS 2.
A good starting place would be making the teleportation range based around the caster, not around the target, or at least require LoS from the caster to the final destination.
Doesn't there already have to be LoS? It sure seems like there is from the times I've cast it.
I guess the idea I had for increasing the AP cost of Teleport to 4 AP doesn't fit with the idea to just make it worse overall for non-mages.