D.Spetz

Only being able to target someone named Will is great. If you want to go for a more classically evil Wish interpretation, you could have the Wizard lose access to any spells that aren't cantrips. Then he would, by definition, cast all of his spells at will.

Check out en.wikipedia.org/wiki/… . Essentially a modern solution to long term solar power storage. Use mirrors to superheat salt, and then store it in giant thermoses until you need it to produce steam. The tech level should be just enough to make this feasible, with plenty of room for improvement

I would consider one more category of traps: Status Affecting. Traps that can poison, blind, etc. can be used to great effect here. Fighter triggers a poison gas trap, and even if he can pass the Fort save the rest of the party is going to be on the other side. You could also use magic traps that require Will saves, which is a Fighter's bane already, for spells like Blindness or Daze. Traps that use Ref saves are also ideal, since it would reinforce that your Dex PCs like the Rogue should be dealing with them