Here is my ideas for them. I am doing this assuming FP is stuff you do to help friends.

Twilight Sparkle: (Well rounded in attack, defense, and energy, Has a combo with spike.) Magic Blast: [-5EP] You shoot a big ball of magic, damaging all enemies. Defensive Study: [-7EP] Next attack is the same one that damaged you last. Stonewall Spell: [-8EP, -1FP] You greatly increase the defense of a party member.

Applejack: (Good attack, Okay Energy, Not-so-good defense) Apple Bonk: [-7EP] You buck an apple at an enemy, damaging it, and sometimes stunning it. Lasso: [-10 EP] Lasso an enemy, making it unable to move (Attack or run away). Apple: [-2FP] You give an apple to a party member, restoring some health. Country Rule: [-9EP] Automatically counterattack when an enemy attacks a selected party member. Applebuck: [-20 EP] Kick an enemy with all you've got! Causing tons of damage, but leavin' you mighty beat also.

Rainbow Dash (High EP, great defense, less damage. Combos with Fluttershy) Thunder Zap [-4EP] Bring over a cloud and zap whatever unsuspecting chump is underneath (You pick what enemy to zap), Tornado [-10EP] Sucks up all enemies, along with whatever large, potentially harmful objects lie nearby. Damages all enemies. Leave her alone!: [-15EP] "Pick on  sompony your own size!" Strongly counterattack any enemy that attacks Fluttershy. Sonic Rainboom [-20EP] "Hey! A sonic rainboom! Wait...Is it just me or is that rainbow coming right at-" -The grunt we tested this attack on. Do a sonic rainboom the sound harms all enemies, and charge at an enemy with blinding speed.

Fluttershy (Low attack, low defense, high health, high FP) The Stare: [4EP] Lower an enemy's defense. Get Help! [-6FP] Tell your little animal friends to get reinforcements. (Either gives all party members some health, or brings in the bear to attack once. Returning the favor he owes Fluttershy for his massage) Cheer: [-6FP] Restores health to whoever you want. Please wake up! [-15FP] Using this gives you a chance at reviving a fallen party member. Costs nothing if it doesn't work. Verbal Smackdown: [-20EP] Gather all your courage and tell that meenie hurting you, and your friends a good, stern, yelling at talking to! Lowers attack, defense, and causes some enemies to run away.

Pinkie Pie (Highest energy, good attack, okay defense) Party Cannon: [-5EP] I fire my party cannon! Woo! Wait, wouldn't the confetti be hot when it shoots out? That might hurt, a lot! Gummy: [-7 FP] I recklessly endanger Gummy's life by throwing him at those big meenies! Don't worry though, I was only kidding. He will just snap at the enemy I throw him at! Scaring him, AND Making his attack miss more often! Surprise! [-7EP] I give the enemy a present! What's inside? And why do I know how to make explosives? Well, you never asked  before silly! One-Pony-Band: [-14EP] I play my one pony band set! But nopony seems to get it...It confuses some enemies, which is okay too. Mirror Pool: [-25EP] FUN!FUN!FIN!FUN!FUNFUNFUN!FUN!FUN! I use my mirror pool counterparts at rush the enemy one at a time! Be sure to hit the attack button when they hit the baddie though! Missing will cause the attack to stop!

Rarity (High FP, Helps Spike, low attack, high defense, moderate health) Whine: [-4EP] Complain to your enemies about their unacceptable behavior, lowering their defense (They want this to be over quickly) and makes some run away. Tom [-6FP] Bring your beloved tom to the battlefield. Making him a potential target for attacks. Kiss [-6EP, -3FP] Give little Spikey-Wikey a kiss. Boosting his defence, attack, and restores his health. Dress up: [-7FP] Make something fashionable for your selected friend. Buffing all stats (Similar to Spike, but less gross, and a little less than Kiss) Diamond Dust: [-11EP] Diamonds are practically unbreakable, they can also be sharpened, and thrown. Damages some enemies.

ALL MANE 6: In boss battles, or when severely under-level, and all are alive. Can use the elements of harmony. Takes away just about all EP from them. But can turn the tide of a very difficult battle.

Spike (Low health, okay attack, high energy, high defense) Take a Letter: [-3EP,and FP from both him and Twilight] Write a letter to the princess. In a turn or two an air strike will be issued. Damaging all enemies. Run Rarity! [-6EP, 4FP] Defend your princess. Counterattack as many enemies that attack Rarity. Fire Breath: [-10EP] Breathe fire...'nuff said. Damages one enemy, and burns them, dealing out damage over time. Jacktail: [-15EP] Use your tail as a jackhammer. A strong attack that is immune to enemies' buffed defense.

Iron Will (High Attack, High Defense, High energy. But lower health. Helps Fluttershy) Bodybuild: [-4EP and FP from you, and whoever you select] Buff somepony's attack and make them tough as nails with your quick and easy routine. MONEY BACK GURRENTEE! Body Slam [-6EP] Slam down with all your weight! Piledriver [-10EP] WHEN SOMEPONY TIRES TO BLOCK! SHOW THEM THAT YOU ROCK! Piledrive an enemy. And look cool doing it! Deck: [-8EP] Sometimes you need to solve a problem by PUNCHING SOMEPONY IN THE FACE! Counseling Session: [-10FP, and 8EP] Boost Fluttershy's morale, giving her a big attack boost. AND giving her the ability to use bodyslam, deck, and piledriver for the rest of the battle.l

BigMac: (Exactly like her sister. But with higher defense, and attack.) Eeyup/Nnope: [-1EP] Give out a flat response to an enemies' monologue. Random status will be applied to a random enemy. Cider: Like the apple, but gives more health. Reason: [-6FP, and 7EP] "Look son, you ain't gonna win. Just back down now." Using this attack gives whichever enemy you use it on a slight chance of running away on it's turn. Applebuck: (See Applejack) Applebonk: (See Applejack)

Doctor Whooves (High health, okay attack and defense) Sonic Screwdriver [-4EP] This attack can temporally disable, or apply a random negative effect to any robotic enemy. This attack can be used to unlock doors outside of battle. TARDIS [-10EP from you, and 5FP from everyone else] Get everypony to the TARDIS to escape from a battle. Yes, even a boss battle! Regeneration: [-20EP] Use your regenerative powers to revive a fallen teammate. If you die, this comes on automatically. Changing your sprite between 2 other sprites. Psychic Paper. [-8EP] Make an enemy tell you how much health he has left, and what it's weakness is.

Octavia (Low attack, high defense. Works with Vinyl) Dischord [-5EP] Use your fancy cherrywood guitar to violently smash an enemy's head in. stunning him. Volatilin (volatile + violin) [-7EP] You need to tune this baby, luckily you have an audience's ears to destroy while you find the right key. Duo Concert (With Vinyl) [20EP and 15FP from you and Vinyl] Sweet string melodies to heal your friends meets powerful wubs to greatly harm your enemies.

Vinyl Scratch (High attack and Low defense. Works with Octavia) Bass cannon [-7EP] Use your wubs to wham a selected listener. Duo Concert (See Octavia)

Zecora (High Defense) Poison Joke. Applys a random effect. Only with more severe damage. Can also confuse, shrink, and blind an enemy. 

Shining Armor (Very high defense, good attack) Cadence toss [-10 EP] Throw your beloved wife at an enemy. knocking him over. Using it's turn to get up. Don't worry, she'll be fine. They do this all the time. Power of Love: [-30EP and 25FP] Like the elements of harmony, only you only need Shining alive to activate. It's a good backup.