Well, to determine if it's a feminist novel, one would need to analyze elements like the agency of female characters, the treatment of gender issues, and the overall message it conveys about women's rights and equality. Without having read it, it's hard to say for sure.
In some fanfictions, Aang's connection to his past lives plays a crucial role. He could draw on the wisdom and skills of previous Avatars. They might guide him on how to defeat Azula specifically. He could learn a new bending technique from one of his past lives that gives him an edge over Azula's firebending, like a unique way of using water to extinguish her most powerful fire blasts.
The development of Katara and Aang's love story was a slow - burning one. In the beginning, Katara was more focused on her own waterbending skills and helping Aang fulfill his Avatar duties. But as they encountered different cultures and fought against the Fire Nation, they became closer. Aang's spiritual side and his determination to bring peace impressed Katara. Katara's compassion and her ability to heal also made Aang fall deeper in love. Their love story was intertwined with the fate of the world they were trying to save.
He might start by observing. Aang is a curious person, so he'd likely watch how people live, how they interact with technology. He may also try to find other benders to learn about any new developments in bending. And he'd probably use his kind heart to make friends easily in this new future environment.
Aang's age in the comics varies depending on the specific storyline, but generally, he is depicted as a bit older than in the original animated series.
In most of the comic series featuring Aang, he is around 12 to 14 years old. This age range is maintained to continue his adventures and growth as a character.