Arya Stark would be an excellent choice. She has already had a great character arc in the original series. In a fanfic, she could use her skills as a Faceless Man to infiltrate different courts and kingdoms, working towards a greater good. Maybe she's trying to prevent a new war from breaking out or uncovering a dark conspiracy that threatens all of Westeros.
Another option could be Sansa Stark. She has become a shrewd politician in the original series. In a fanfic, she could use her intelligence and influence to reform the laws of the kingdoms. She could be the one to introduce new systems of governance that are more fair and just, especially for women and the lower classes, and face resistance from the traditionalist lords.
Jon Snow could also be the main character. He could continue his journey of uniting the wildlings and the people of the Seven Kingdoms. In a 'to go forward' fanfic, he might face new challenges like dealing with the aftermath of the Long Night and trying to rebuild a shattered Westeros while also facing political opposition from the remaining noble houses who don't trust him.
Perhaps a fanfic could focus on the dragons growing even more powerful and intelligent. They could start to communicate with their riders on a deeper level and help shape the future of the Seven Kingdoms. Daenerys' dragons could form alliances with other magical creatures in the land, like the Children of the Forest, to bring about a new era of peace and prosperity.
A lost princess from Westeros who washes ashore in Ulthos. She quickly realizes that Ulthos is a land full of secrets and danger. With her charm and the political knowledge she learned in Westeros, she tries to navigate the complex power structures in Ulthos and make a name for herself.
Perhaps the main character could be a female machinist. In a world dominated by men, she has to fight against prejudice while also using her skills. She could be from one of the noble houses but has a secret love for machinery. She might be working on a project to build a flying machine, which is seen as crazy by others, but she is determined to prove them wrong and change the face of warfare in Westeros.
A demon who has taken on human form could be the main character. He could be disguised as a knight or a noble, secretly using his demonic powers to influence the events in the Seven Kingdoms.
A Stark could be a great main character. They are known for their honor and loyalty. A Stark warden would have to deal with the aftermath of the War of the Five Kings and try to rebuild the North. He or she would face challenges like dealing with the Boltons, who had previously held power through treachery. Another option could be a Tyrell. The Tyrells are a powerful family and a Tyrell warden would be involved in the complex politics of the Reach, like dealing with the High Sparrow's influence.
It could be Jon Snow. He had to grow up a lot in the series and leave behind his more boyish ways. In a fanfic with this title, it would make sense for him to be the main character as he constantly had to make tough decisions that forced him to shed his innocence.
A young girl from a small village near the Wall could be a great main character. She could be an orphan who has a special connection with nature. One day, she finds a dragon egg while exploring a cave. She has no idea what it is at first, but she feels drawn to it. As she takes care of the egg, she starts to develop powers of her own that are related to the dragon's magic. Eventually, she hatches the dragon and becomes a powerful figure in the North.
Arya Stark could be a great main character. With her skills and determination, in the ROS Daisy context, she could gain some new powers or abilities. Maybe she discovers a Daisy - related magic that enhances her already formidable skills in stealth and combat. This would make her even more of a force to be reckoned with in Westeros.
Well, it could be explosive. The Dragonborn is a powerful figure, and Joffrey is a bratty, power - hungry king. If they met, the Dragonborn might not tolerate Joffrey's rudeness and abuse of power for a second. They could use their dragon to intimidate Joffrey right away.
Arya Stark could be the main character. If she ended up in Braavos but in a situation where she had to interact with the high society instead of the Faceless Men, she would be like a fish out of water. She's a street - smart girl from Winterfell, and now she has to deal with the complex social hierarchies and etiquette of the Braavosi elite, which would be a huge challenge for her.