Alright, moar in-depth review time because I'm not on a phone. Hooray!
I'm going to assume by the 'Storm' and 'Slide' powers you're referring to the charging run in ME1 and the ME3 evasive move, respectively. Those aren't really powers, per say. The powers we're referring to are anything that you could pick from the radial menu or hot key to use in-game related to class. As Sunny D mentioned, you can have more than the one power. Your character's 31 years old; he's obviously fulfilled some kind of function in the Floatilla that would give him some kind of specialty. Was he a marine? Someone related to the operation of a ship? Repair guy? Navigator? Food production? There's literally nothing to go by.
As well, given how tight-knit quarian communities are (you literally can't exist in quarian society without interacting with people; their "houses" are basically cubicles in large rows, and you don't buy things, you take what you need from the "marketplace" and return what you aren't using for somebody else to use). It's meant so it feels inclusive and that you're a part of something bigger and more important than individual needs. This is why it doesn't really make sense for Shortar to become rebellious and resentful over his mother's death. It is literally an event he could not remember (childbirth) and he had far more than his father raising him. The way you wrote everything kind of makes it seem like he spent the better part of two decades being an anti-social, rebellious individual who was prone to acting out without maturing. This is a part of the reason actually fleshing out the sheets matters; it not only gauges your writing ability, but it also establishes a believable and well-thought out character. To be blunt, it kind of feels rushed as it is, and it's very, very short on the details. Look at the other accepted character sheets to get an idea of what we're looking for.
From what I take from the Bio, Shortar was exiled before his Pilgrimage, which would be an incredibly harsh punishment for a child. As mentioned, it's like the death penalty. Imagine sending a 13-14 year old kid to death row for trying to steal a car; it's pretty much exactly the same thing. The quarians probably wouldn't be overly harsh and consider it a failure on their part to have effectively help raise the kid that would make him take such drastic actions. They'd almost certainly try to rehabilitate him over saying "well, he's a write off" because once again, quarians can't afford to lose their population, especially over something that's done by a kid who was acting out. It's not like he sabotaged the drive core of a ship or screwed with the life support or anything. He tried to steal a ship; since he didn't succeed, there's no way to know what his intentions are. Also, since it's a fighter, it's not like it has a very long range or FTL capabilities, anyways. There's a reason that humans make a big deal about coming up with the idea of assault carriers to worm their way around dreadnoughts, because they have an effective means of transporting fleets of fighters to a battle and deploying them en-mass. It's not like they can accompany the bigger ships with much better propulsion capabilities and fuel capacities from point A to point B when we're talking galaxy spanning distances, or even solar systems.
As Sunny D mentioned, how would he have learned how to use a sniper rifle, or have a preference for a high-recoil hand cannon if he had no formal training in either? The Carnifex would be like having a Desert Eagle in a lot of ways, given its large size, powerful shot, and hand wrecking recoil. A presumably non-physically fit and combat trained kid would have a hell of a time using either, especially something that requires a particular amount of dexterity and technical skill to use as a sniper rifle, which even with ME's advanced targeting systems, still involves holding your arms steady and being able to handle a heavy, cumbersome weapon to put a single shot on target at long-range.
Finally, where's the information on his exile? You wrote down a very brief bit about his childhood, but it doesn't really go into much about his upbringing, his relationships, or anything of the like. It doesn't have to be super extensive, but think about your own life and what shaped you into who you are, similar things should be considered for your character. Not knowing what he's been doing for literally over half his life is also kind of a point of concern; where did he go as an exile, where did he find food? How did he keep his suit intact and operational? How was he earning money? Keep in mind this is a kid with very little hard skills to offer, and quarians are pariahs in the galaxy, it's hard for them to find any kind of meaningful work when they're trained pilgrims, let alone a school age kid who tried to steal a ship he didn't know how to fly. Plus, a big one, why would Nova ever want to pick him up as a new hire?
Anyways, you have a foundation to flesh out, but I strongly suggest you look at the other character sheets and the In-Character section to kind of get an idea of what we're looking for. If you think you can have comparable writing, great! Take some time to really iron things out and make it convincing. Otherwise, you might have a really hard time keeping the pace. Don't be discouraged! We're more than willing to work with someone willing to put in some honest effort. Most of what I was writing is pointers for what to address and build upon, not to discourage you. Part of doing a GMly thing.
I mean, I hope I figured out the GM thing by now. My other game's been running for over a year and this one's about two months away from its anniversary.