Yes, I always encourage people to come up with their own Virtue Flaws even in regular Exalted, and here I especially do. Basically just ask yourself, "If my character was overstressed to the point of a mental breakdown, what would that look like?" and we'll find a way to marry game mechanics to that.
I'm not sure how the Hanged Man got left off that list--tsk, always abandoned, that one--but I'll go back and fix it later tonight. The basic Exalted rules for Favored Abilities apply to Arcana Abilities: you must have at least one dot in your Arcana Ability, and you receive price breaks for using Experience/Bonus Points to raise it or buy Charms from it. That said, it doesn't have to be you highest or most used Ability, though it's a fairly good idea to have it at a reasonably high level, since your Persona's main attack skill (Melee, Unarmed, Ranged, or Thrown) will be mirrored off it. A minimum of 3 dots is a pretty good idea. Also note that in addition to your Arcana Ability you choose any five other Abilities to also receive Favored Ability status. These Abilities also have to have a minimum of one dot to start out, but otherwise there are no restrictions on your choice here. A person of The Lovers Arcana could, for example, choose Melee, Unarmed, Ranged, Thrown, and Dodge as their additional Favored Abilities. (I'm not sure why you would, but you could!)
That said, you have a lot of dots in just about everything for a high school student. Keep in mind that you aren't Exalts, and there aren't any running around in this setting; you aren't comparing yourself on the scale of earthbound gods. A rating of 5 dots is basically as good as it gets at whatever that is, and even 3 dots is a fully professional level. A character who has 3 dots in Athletics and an appropriate Specialization or two could easily be a star player on the team; a rating of 4 basically means a guaranteed scholarship and possible pro career, and a 5 means you may someday be the best in the world. A character with 3 dots in Academics is probably at or near the top of their class and will have no problem passing college entrance exams, while a 4 is at or near the top of the school, and a 5 is Light Yagami-type "genius" student status.
For Attributes, a 2 is middle-of-the-road, while a 3 is above (adult) average; a high school student with 3 Strength or Manipulation is nothing to scoff at. Again, a 4 or 5 is very impressive. There's an expectation here that your characters, as the protagonists, are more than just run-of-the-mill average students in some regard, though it's largely up to how you decide to use your Bonus Points what that is. They could be star athletes, superb academics, art prodigies, or something a bit more esoteric--for example, a character who spends Bonus Points mostly on Virtues and Willpower might be hard to define in such simple labels, but there's certainly something special about him.
If you did want to play a fairly normal high schooler, the best way is probably to spend your Bonus Points on Social Links and additional Essence/Charms for your Persona. You'd still be uniquely talented, just not in a way normal people would ever be able to perceive.