So, we have these two spells, Cause Fear and Doom.
They're the same level.
They are both single-target.
They are both Necromancy.
They both have a Will save.
They are both Fear effects.
They are both resisted by Spell Resistance.
Cause Fear costs 6 sp, Doom costs 4.
Everyone who gets Doom as a spell also has access to Cause Fear.
Cause Fear makes an enemy Frightened, and if they MAKE a will save they are then Shaken and get a -2 to attack rolls, saves, etc.
Doom makes any enemy Shaken if they FAIL a will save.
Why. Why. Why. WHY. would you EVER use Doom, since it does, on a FAILED save, what Cause Fear does on a SUCCESSFUL save?!
With as few spells as there are in the game, why are so many of them redundant and/or completely useless?!