here i have few suggestions for magical and faith abilities :
Magic :
-Stone Shock : makes enemy stuck in place for (x) seconds.
-Finger of Death : one shot one kill but you take half of the damage dealt with this spell.
-Equilibrium: costs health to add in some extra magicka.
-Bolide: flaming rock that heats up as it travels dealing bonus damage based on distance.
-Slay Living: necromantic blast that destroys enemies below 25% Health.
-Wildfire: burns a target dealing gradually increasing damage on subsequent hits.
Faith:
-Purification: heals you and damage nearby undead at the same time.
-Repel: you gain spell immunity for (x) seconds.
-Degen Aura: degenerates movement and attack speed of all enemies nearby.
-Guardian Angel: you gain physical damage immunity for (x) seconds.
-Serenity: you are immune to all knockback effects from all kinds of attacks.
-Divine Strenght: you gain (x) points in Ironflesh,power strike and power throw for (x) seconds.
-Steed Charge: your horse gain speed and charge damage for (x) seconds.
anyways i dont think some of these abilities are gonna be possible to add with m&b engine.but those are just some ideas to work with

. the (x) means a random number since i dont really know how to balance things so yeah.