Hi, Luis --
First, your "broken English" is excellent! If you didn't say anything I would not have guessed you aren't a native speaker.
Here are a couple of ideas you might explore for increasing the "magic is rare" element in Primeval Thule:
* No cantrip attack spells; encourage the PC spellcaster to default to dagger, dart, or even thrown vials of acid/alchemist fire when he wants to attack without expending a spell slot. If the caster *looks* like spends 30 or 40 percent of his actions using sly, underhanded "wizard weapons" instead of blasting pew-pew-laser, it changes the tone of the encounter.
* Add a "level tax" to spells of extremely "loud" magic schools. Maybe evocations or transmutations are harder than illusions and necromancy. Casters work through deception and curses, they don't blow things up or turn people into frogs.
* Add a cost: more sanity rolls, spending hit points to cast, picking up levels of exhaustion if you cast too many spells too fast.
All of these ideas make a wizard (or sorcerer, or what-have-you) strictly weaker than they would be otherwise, so I might make up for that by providing some special skill use for Intimidation or Knowledge. People might be *terrified* of magic and the wizard can daunt them easily. Or maybe you can borrow some of the knowledge-based "help my party fight better" abilities like the Archivist from Heroes of Horror. It's a different class at that point, but I think you would feel a lot more like a wizard in a Conan story and less like a superhero.
Hope that helps--and I'll say you've given me an idea for something we ought to touch on the next time we work up some Thule player content!
Oh, and for the GM Screen, send a note to sasquatchgamestudio. We can probably help you out.
Rich