One key element is his origin as a Demon Scythe. Another is his pairing with Maka. His growth in terms of controlling his weapon abilities is also important.
One great Crona x Soul fanfiction is 'The Bond Beyond'. It delves into how Crona and Soul's relationship develops in a more in - depth way than in the original series. It shows them learning about each other's pasts and how they grow together. Another one could be 'A Different Kind of Friendship'. This fanfiction focuses on how they start as friends but there are hints of deeper feelings emerging as they face various challenges in the world of Soul Eater.
Soul's back story involves him being a Demon Scythe. He originally came from a place where weapons have their own kind of existence. He paired up with Maka to form a meister - weapon team. He has a cool and somewhat laid - back personality, but beneath that, he has a strong will to fight and grow stronger along with Maka in their journey to collect souls.
I think it is. The plot has depth, the action scenes are exciting, and it has a good mix of humor and drama. However, it might not be for everyone depending on personal preferences.