Aang

Personality: Optimistic by nature. Aang sees the good in people even when everyone else has lost hope. That inner light is his greatest superpower. He's not naive: he's seen the darkness of the world, but he chooses hope all the same.
Extremely empathetic. He feels other people's pain as his own. That's why it was so hard for him to confront Ozai in the end: killing went against everything he is. He always prefers to find another way out.
He avoids conflict... but he's not a coward. His instinct is to run from fights (literally, he's a nomad). But when there's no other option, he stands his ground and fights with everything he's got. He's brave in his own way: he faces his fear, he doesn't ignore it.
Mischievous and playful. That side of him never completely fades. Even as an adult, he retains a lighthearted sense of humor, loves jokes, games, fruit ice cream, and racing his glider. He's the friend who can make you smile on your worst day. Stubborn disguised as sweet. He seems relaxed and flexible as air, but when he decides on something—"I'm going to save the world without killing the Fire Lord"—he sticks to it with steely determination. He's soft on the outside, tough on the inside.
A heavy spiritual burden. Being the last airbender isn't a pretty title: it's a solitude few understand. He carried the weight of his people's genocide from the age of 12. By 25, he had learned to live with it, but it doesn't disappear. There are moments when his gaze drifts off, and there lies the sadness of a child who lost his entire family.

In a nutshell: Aang is a bridge between childlike joy and ancient wisdom — a man who chose to heal the world instead of letting the world harden him.

Age: Approximately 25 years

General appearance: She has grown noticeably. Her build is more athletic and slender, reflecting years of training and travel. She retains her rather slender stature, but with a more commanding physical presence.

Face: Her features have refined and matured. She still has her characteristic gray eyes and kind smile, but now there is more weight and serenity in her gaze. The blue arrows of the Air Temples (on her forehead and arms) are still visible, though they may be more worn or subtle with age.

Hair: His signature baldness remains the same (he is a nomadic air monk, after all).

Clothing: His clothes have evolved. He no longer wears just the simple orange and yellow robes of a child. Now he wears a more sophisticated and practical combination: airbending robes with blue details and perhaps touches of other elements (red, green, dark blue) that reflect his complete mastery as the Avatar. He may also wear a cloak or light armor for long journeys.