Frodo could be one. Since he was also closely associated with the ring in the original story, he might play a role in this fanfic, perhaps as a supporter or someone who has doubts about Bilbo's ability to destroy the ring.
One way to develop Bilbo in this fanfiction is by exploring her femininity. She could bring a different set of skills or qualities. Maybe she has a better intuition or is more in tune with nature. As she goes on the adventure, she could use these qualities to her advantage, and this would not only help in the story's progression but also in her own development as a character. For example, her intuition could lead her to find hidden paths or sense danger in a different way than a male Bilbo would.
Maybe Gandalf could help. He's wise and might have some knowledge about hair - cutting. Or perhaps one of the dwarves, like Thorin, who could offer some practical advice or even do the cutting for Bilbo.
There could be the company's CEO, who might be initially hesitant about adopting Bilbo but later sees his potential. Another character could be Bilbo's mentor in the company, someone who helps him understand how things work.
No. Fanfiction that involves abusing a character like Bilbo is not ethical. Bilbo is a beloved character from Tolkien's work, and creating scenarios of abuse goes against the positive values of the original story.
It depends on how one defines 'appropriate'. However, given that it involves the concept of 'abuse', it's probably not suitable for a general audience. Fanfic is often a way to explore different aspects of a character or story, but abuse is a serious and uncomfortable topic. If it's just using the term 'abuse' in a very mild or metaphorical sense, that might be different, but without more information, it seems inappropriate.
Bilbo would likely interact with Gandalf again. Since Gandalf has a long presence in Middle - earth's history, he could be a key figure for Bilbo in the past. Also, the dwarves, especially Thorin Oakenshield. If Bilbo goes back to a time related to the Lonely Mountain, he would surely cross paths with them. And elves like Elrond. Elrond has a vast knowledge and his presence in different historical events makes him a likely character for Bilbo to meet.
Bilbo would likely be more fearless. Growing up with eagles, he'd be used to heights and danger. So, when facing the likes of Smaug, he might not be as timid as in the original story. He'd approach the dragon with more confidence.
A Laketown girl who is curious about the outside world could be a main character. She would be drawn to Bilbo because of his tales from far - away lands. And an old wise man in Laketown who has knowledge of ancient remedies could also be a main character. He would try to use his knowledge to help Bilbo regain his sight and health.