Those are some good ideas but I don't understand why they have different pip costs. I like the idea of storm taking damage to deal heavy damage, it really fits with the unpredictably but raw power of the school. Here are a couple of ideas:
School: Storm Pip: 8 Name: Lightning Beast Effect: A huge cloud of grey smoke funnels over the top of the arena, a roughly humanoid crouched over gigantic form made primarily of electricity drops out. It begins to spin and a huge pops of blue light appear everywhere as the screen shakes. It deals 1,015-1,135 storm damage to all enemies and to you, and ignores storm resistance. You are stunned for a turn.
School: Fire Pip: 8 Name: Great Dragon Effect: The middle of the arena crumbles away and an enormous dragon head pokes up. After a moment, it breathes fire on the enemy you chose, dealing 950-1,045 fire damage. All enemies take 300 damage over the next three turns.
School: Ice Pip: 8 Name: Permafrost A white spot appears at the center of the arena, then it creeps outwards faster and faster and snow starts falling down. At the end the arena shines with blue light and all enemies are frozen solid, and all friends are covered in snow. All friends and you gain a -80% to next damage shield, and all enemies are stunned for two turns(frozen), in addition to taking 400 ice damage.
School: Death Pip: 8 Name: Graveyard Effect: Gravestones sprout out of the ground everywhere, dark clouds cover the top of the arena, and zombies/ghouls start climbing out of the ground(probably 6) and start running at the enemies. each enemy takes 785-865 death damage, and then the ghouls randomly fire blasts of healing at all friends(one blast per ghoul, each heals 1/12 of the total damage dealt by graveyard, each has a random target)
School: Life Pip: 8 Name: Tree of Life Effect: A huge blossom tree(like the Life Tree in Ravenwood) sprouts and heals for 1,300-1,395 life, plus an additional 50 life healing every turn, for every friend.
School: Myth Pip: 8 Name: Titan Effect: Summons a Titan minion. This is a rank 8 minion, and it knows Storm Lord, Seraph, Pixie, and Surge(zero pip balance spell, usually found only on wands)
School: Balance Pip: 0 Name: Power Overflow You turn all of your normal pips into power pips, and gain new normal pips for every power pip you already have before you cast this spell. This spell can only be cast once per fight, no matter what.