In my opinion, the Ranger class can be great for the story in Deadfire. Rangers have a strong connection with nature which often ties in well with the game's themes and story elements. Their animal companions also add an interesting dynamic to the story progression.
Xoti's story is quite remarkable as well. Her faith and her role as a priestess are central to her character. Her journey with the Watcher is filled with moments of self - reflection and growth. The way she deals with the darker aspects of the world while maintaining her positive outlook is a great part of her story.
Pallegina has a very unique story too. Her connection to the Vailian Republics and her sense of duty are central to her story. Her conflicts between her personal beliefs and the orders she has to follow add a lot of intrigue. Also, her cultural background gives a different flavor to her story compared to other companions.
The Cipher class can be really good for the story too. Ciphers have this unique mental power that can be used to understand the minds of others and manipulate them. This power can lead to some really interesting story developments as they interact with different characters in the game.
Well, for me, a great backstory is key. If a companion has a rich past filled with events that shaped them, like Eder's time in the war, it makes their story interesting. It gives a context to their actions and attitudes in the present of the game.
Aloth is another character with a fascinating companion story. His struggle with his own identity, being a wizard with a dual personality, is a central part of his narrative. His journey to come to terms with himself and his place in the world makes for a great story as you play through the game with him.
Hearts cartoons in black and white usually have a simple and classic look. They might focus on the shape and outline of the hearts to convey the emotion.