Ty Lee has gray eyes, which is an air nomad trait. Aside from

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Ty Lee has gray eyes, which is an air nomad trait. Aside from a couple of characters who I can't recall, Aang is the only one in the show with gray eyes.
Ty Lee's face is very round, similar to Aang's. Looking at other air nomad characters, it appears to be a commonality. Also, Jinorra looks a lot like Ty Lee, as does her mother Pema.
Her personality matches Aang's so well that it's almost as if she is the female Aang. Both are very excitable, care-free, happy, outgoing, and social. Not to mention, they smile a considerable amount.
Ty Lee is incredibly quick, agile, flexible, fast, and capable of jumping very high. Aang shares those abilities as well.
The Air Nomads were, obviously, nomads who didn't settle in one place for too long. Ty Lee moved from home, and then from the circus, very quickly. Of course, this isn't a strong bit of evidence.
Her fighting style appears to minimize the amount of pain she deals to an opponent, which is an extension of her gentle nature, which is an extension of the Air Nomads.
Here's a trivial bit of evidence. In "The Beach", Ty Lee is the only one of the four teenagers who wears a white swim suit. Perhaps Zuko, Mai, and Azula wore crimson as an extension of the Fire Nation and Ty Lee wore white in respect to the Air Nomads?
This one is very peculiar. Ty Lee is spiritually aware with her ability to see auras and feel the energies (recall her negative energy reference). The Air Nomads were incredibly spiritual as well. I believe Guru Pathik and Iroh may have been the only other characters who can say the same.
She's also not a Firebender, though she is obviously (mostly?) Fire Nation by blood.
If she is part Air Nomad, it wouldn't be by much, but it's an interesting theory nonetheless. What do you think?