Twilight Sparkle: Commander Sheppard (FemShep) | Rainbow Dash: Ashley | Comet Tail: Kaiden | Spike: Joker | Fluttershy: Tali | Rarity: EDI | Big Macintosh: Wrex | Flash Sentry: Garrus | Applejack: Miranda | Vinyl Scratch: Jack | Pinkie Pie: Liara | Bulk Biceps: Grunt | Soarin: James | Sunset Shimmers: Samara | Cheese Sandwhich: Mordin | Derpy: Legion | Dr. Hooves: Thane | Braeburn: Jacob | Lyra: Kasumi | Troubleshoes: Zaeed | Zecora: Javik | Bon Bon: Kelly Cahmbers | Nurse Redhead: Dr. Chackwas | Octavia: Samantha Traynor
The Alliance:
Celestia: Anderson | Luna: Hackett | Fancy Pants: Captain Bailey | Hoity Toity: Admiral Mikhailovich | Mayor Mare: Ambassador Udina
Villains:
Blueblood: Saren | Discord: The Illusive Man | Lord Tirek: Harbinger | King Sombra: Sovereign| Lighting Dust: Kai Leng | Trixy :Aria
That's just my opinion. If you have better ideas, you know what to do. All I ask is this: Please, do not freak out if any of those ideas don't suit you