I think Wyll has a very engaging story. He made a pact with a devil, and his struggle to break free from that pact while still trying to do good in the world is full of moral dilemmas. His origin story shows how he got into this situation and his continuous fight against his own dark side.
For me, it's Gale. His story involves his relationship with magic and a dangerous artifact he has. He's constantly grappling with the consequences of his past actions regarding this powerful object, and his journey to either redeem himself or face the consequences is fascinating.
In my opinion, Lae'zel has a very compelling story. She is a Githyanki warrior, and her story is full of her people's culture, honor, and the struggle against Vlaakith. Her loyalty to her race and her slow realization that things might not be as they seem in Githyanki society is really interesting. It's also cool to see her interact with other characters from different backgrounds and how she adapts or clashes with them.
I think it's Lae'zel. Her story is centered around her Githyanki heritage and her strict military upbringing. She has very strong beliefs about her race's superiority at first, but as she travels with the group, she begins to question some of those long - held ideas. It's really interesting to see her grow and change as she experiences different cultures and situations outside of what she knew in her homeland.
For me, it's Lae'zel. Her unwavering loyalty to the Githyanki cause at first, which then gets shaken as she experiences different things in the world, is really fascinating. She has a lot of pride in her race but also starts to question some of their ways, and this internal conflict makes her story stand out.
I think Astarion has one of the most engaging stories. His vampire nature gives him a dark allure. His backstory of being tortured by Cazador and his attempts to gain freedom while also dealing with his newfound vampiric powers makes for a really gripping narrative. It's full of twists and turns, and his character development throughout the game is fascinating.
The Half - Elves. They are a blend of two races, and this often leads to a sense of not fully belonging anywhere. In the story of Baldur's Gate 3, this can be explored in many ways. For example, they might have to choose between the cultures of their human and elven sides, or they could be shunned by both. This inner conflict and the search for identity can create a very engaging story as you progress through the game.
Shadowheart also has a great origin story. She's a cleric with a mysterious past and a mission she's not entirely sure about. Her loyalty to her goddess is tested throughout the game as she discovers more about herself and the truth behind her orders, which makes for a really engaging story.
Astarion has a great origin story. He's a vampire spawn with a complex past of abuse and manipulation by his master. His journey of self - discovery and breaking free from that control is really engaging.
The Githyanki origin story is great too. You are part of this warrior race with a rich history and culture. It gives you a different perspective on the game world. You have unique abilities and interactions based on your Githyanki heritage. For example, your connection to Vlaakith and the whole Githyanki society can lead to some interesting storylines and interactions with other characters who may be in awe or fear of your race.
The Cleric is a good class for the story. Clerics are the servants of their deities. Their religious beliefs and powers can be a major part of the story. For example, they can perform religious rites or seek the guidance of their gods. In times of trouble, they can use their divine magic to heal and protect, which can play a significant role in the story's development, especially when the group faces difficult challenges.