Cinderella would be a central figure. For the male lead, it could be a young and noble - hearted character like Robb Stark. He has the charm and leadership qualities similar to a prince. The stepmother could be a power - hungry noblewoman, like Cersei Lannister in some ways. The stepsisters could be her daughters, who are jealous of Cinderella's beauty and the attention she gets from the young lord. And then there could be other 'Game of Thrones' characters like Tyrion Lannister as a side character providing some wisdom and humor.
In this fanfiction, Cinderella is the main character. As for the male lead, it might be Jon Snow. He has that mysterious and heroic air about him. His story of being an outcast could parallel Cinderella's in some ways. The stepmother could be a cruel noble from a minor house who wants to use her daughters to gain power. The stepsisters would be her tools in trying to outshine Cinderella. There could also be characters like Daenerys Targaryen in the background, whose actions and conquests would affect the political situation that the other characters are in.
It could be really interesting. Imagine Cinderella in the world of 'Game of Thrones'. She might be a common girl in one of the kingdoms, perhaps King's Landing. Instead of a glass slipper, she could leave behind a dragon - shaped brooch. And the prince could be more like a young lord in Westeros, with all the political intrigue and power struggles around their relationship. Maybe the fairy godmother could be a powerful sorceress like Melisandre, but with a kinder heart.
Daenerys could be a main character. She has leadership skills and her dragons could be a huge asset in a war - like scenario inspired by WWI. Another could be Jon Snow. His experience in leading the Night's Watch and fighting the White Walkers could translate into him being a key figure in this fanfiction's battles. Tyrion Lannister would also be a likely main character. His intelligence and ability to strategize would be very useful in a complex situation like a WWI - style conflict in Westeros.
It could be a new character created specifically for the fanfiction. This character might be an outcast from a noble house who receives the call and is thrust into the center of the power struggles in Westeros.
Often, the Gravewalker themselves is a main character. They usually have a mysterious past and special abilities. There could also be characters from the original Game of Thrones series who interact with the Gravewalker. For example, Jon Snow might cross paths with the Gravewalker and they could form an alliance or be at odds. Daenerys could also be involved, perhaps seeing the Gravewalker as a threat to her claim to the Iron Throne.
In some fanfictions, Jon Snow could be a central figure when combined with the angel elements. Imagine an angel bestowing upon Jon some new powers or knowledge that helps him in his fight against the White Walkers. And there could be a female angel character who has a special bond with Jon, guiding him not just in his battles but also in his personal growth as a leader.
Often, there could be a young and idealistic character who leads the uprising. Maybe a bastard son or daughter of a noble house who has seen the injustice in the system. Another could be a former slave who has escaped and now wants to free all his fellow slaves. And there might be a maester who has been exiled from the Citadel for his radical ideas and joins the uprising.
A young and clever maid in the service of one of the noble families in Queensgate could be a main character. She might be privy to a lot of secrets and use her wits to navigate the dangerous political waters. Maybe she overhears a plot against her master and has to decide what to do about it.
I think Naruto would be like the central hero, similar to how Daenerys was in Game of Thrones. He wants to bring change and justice. Then there's Kakashi, who could be like a wise advisor, much like Tyrion Lannister in some ways. And Gaara, with his past of being an outcast, could be a character who rises above his circumstances, just like Theon Greyjoy did at some points.
There could be a fearless space captain as one of the main characters. He or she might be leading a group of rebels against a tyrannical interstellar regime, much like how some characters in 'Game of Thrones' fought against unjust rulers.
One main character could be a genetically - enhanced human who has special abilities, like Arya Stark's skills in the original. She could be on a mission to avenge her family who were killed by a powerful space - faring clan. There could also be a powerful warlord from a distant star system, a bit like Ramsay Bolton, feared for his cruelty and thirst for power. The interactions between these diverse characters would drive the story forward in this space - based Game of Thrones fanfiction.