Matchstick
Adventurer
Well right now I'm making my game (fantasy scifi type of stuff) for 13th age, which I really enjoy but it's becoming pretty overwhelming (which I assume is natural) so I was looking at other systems. I want something that's easy to create for but the most important thing is that I have specific classes set up. So GURPS and HERO don't really have that, though its easy to just throw together some skills and call it a class or race, and I was wondering how FATE handled that type of play. Additionally I wanted to have a MP based magic system, which is incredibly hard to do correctly in a tabletop game, and was wondering how malleable magic systems are in FATE. Ideally I want something more narrative, which is why I went with 13th age in the first place.
I guess the biggest thing I want is for classes to feel very unique during play. I want my bard class to be able to put different harmonies and melodies together to create different effects for their party. I have androids that function similar to how megaman games work, I have sentinels which are similar to jedi/paladins, my Archons are like the martial artists from dragonball z, my Primus class are like benders from TLA and Korra which use solid, liquid, gas, and energy. My wizards deal with quantum, time, and cosmic (dealing with fundamenal forces of physics), my binary which are my clerics than switch between negative and positive energies. Spectres are my rogues and assassins which function like avengers from 4th edition and assassin's creed games and of course my Blades which are my fighters.
The game takes inspiration from stuff like Numenera, Phantasy Star Online, Final Fantasy series, Chrono Cross and Trigger, mass effect etc etc. How well will fate handle all of this that I have described? I want the players to feel like they are completely different from any other classes. Can fate do this?
Trappings in Savage Worlds would handle most, if not all of those. Savage Worlds just provides the basic statistics for something like a magical Bolt attack, but the character and GM work together to decide how it manifests in game. So Bolt on the Bard might be a sonic attack guitar chord turned up to 11, on an android might be an energy slinging arm replacement, on Korra might be a fire/ice/water/rock/air projectile, on an Archon might be a pale fiery manifestation of Chi, etc. The basic statistic for a Bolt attack is there, but the trapping, how the attack manifests in the game, is completely up to the player (with GM approval of course). If the player wants a stream of hornets to flow out of his/her mouth and attack the bad guy, go for it. Eye beams? No problem. Mechanically all of those things would probably be VERY similar, but the in game appearance could be radically different. I've found that when players write "Mk VII Arm Cannon" on their sheet, they don't care so much when their neighbors "Hadouken" attack does essentially the same damage (and of course characters can spend to make their Bolt better, so even the same damage may not happen).
Core Savage Worlds has differing Arcane Background Edges; you could do your own similar thing if you wanted. Arcane Background: Wizardry, AB: Cybernetics, AB: Music, AB: Chi Powers, etc. Maybe they would be character creation Edges, or you could say only take one at a time, if you want them to be exclusive.
There wouldn't be any classes I guess, so that doesn't fit with your question, but you could limit the Arcane Backgrounds to effectively create classes as mentioned above, and still have your fightery, theify, non-Arcane types. In fact maybe the best way to help classes feel unique is to not have classes; to just offer options and let the players build what their unique vision holds, or as close as is possible.
I'm not trying to shill, Savage Worlds was the first thing that occurred to me, and then I got long winded.

Have fun no matter how you decide to go, it sure sounds like some cool stuff you have going on!