They might make higher tier magic weapons available in similar way as other weapons, but with less power curve. Their use could cost more eitr while having more advanced or specialized effects. Alternatively, they could function identically to currently available magic weapons, but have their own secondary spells with advanced features.

But yeah the frost staff is a bit on the weak side. It's not bad when you actually need to have something slowed down, but that's it. Bad accuracy, and worse damage for durability and eitr cost. It may be much better in ashlands of course.