I think there should be arecipe vendor for certain utility spells beginning at Level 30. Certain spells would be immensely helpful at that point, and frankly I think every school should be able to learn certain utility spells.
Here is a list of things I think this recipe vendor should have:
Mass converts for all schools
Pierce spears (6% pierce)
Mass infection (3 pips for -35% health to all)
Cooldown (2 pips for -1 round of damage over time to all)
others?
These should be difficult to craft (reagent combos should be rare), and I think it should be craftable only in a world-based crafting station (e.g., in Grizzleheim or Dragonspyre).