I must admit it looks good.

Fire powers require flammable material to work right - the oxygen in the air usually suffices

Note: Oxygen is not flammable — it is comburent (oxidizing), it's like a yang for the flammable materials' yin. You can't burn oxygen, but you can burn with oxygen.

Rock - Created rock usually sticks to the user until dissipated, which can be used as a blunt instrument. Otherwise, stone and earth can be manipulated, though not thrown about. Its associated eye/hair colour is brown.

Can another forms of rock (like sand or glass) be manipulated?

Wind - Control of air. Notably, this also applies to the air in the lungs. Wind maja can be exceptional singers because of this. Its associated eye/hair colour is beige.

Could they control the air in another person's lungs? (Like in Butcher's Codex Alera.)