He might become more confident. With the tracer abilities, he can take on more challenges. For example, if he can trace dark magic, he will be more willing to go after dark wizards.
The tracer abilities in the fanfiction might be described as an extension of Harry's existing magical skills. Given his natural talent and his connection to powerful magic (like his defeat of Voldemort), these tracer abilities could be a new manifestation. Maybe he can trace not only spells but also the intentions behind them. So if someone has cast a spell with ill intent, he can follow that intention's 'trace' through the magical environment. It could be a very useful ability in his adventures, whether in Hogwarts or in the wider wizarding world.
In some fanfictions, Harry Potter might absorb abilities through magical artifacts. For example, he could find a special amulet that transfers the powers of the previous owners to him when he touches it.
His character could develop in terms of leadership. As he is building the ship, he has to take charge and make decisions. This would make him more confident in his leadership abilities.
Well, at first, he might be a bit scared and unsure of his new ability to control the weather. But as he starts to experiment, he gains confidence.
Studying ancient magic texts related to serpents might be a way. These texts could contain spells or incantations that can boost the power of snake summoning. Maybe there are also rituals that, when performed correctly, can expand the range of their ability, allowing them to summon snakes from greater distances. Additionally, they could learn from other magical creatures that have an affinity for snakes, like basilisks (if they can find a way to communicate safely), to gain more knowledge about snake magic.
Well, it might enhance his magical power significantly. Dragon blood is often associated with great strength and heat in magical lore. So his spells could be more powerful, like his Patronus might be larger or more vivid. Also, he could have a natural affinity for fire - related magic, being able to conjure and control flames more easily than others.
Some fanfics show characters developing 'legilimens' abilities through intense practice. They might start with simple mind - reading exercises, like trying to sense the surface thoughts of a willing partner. As they progress, they move on to more complex tasks such as reading the deeply buried memories of others.
In this fanfiction, Harry's development could be centered around his understanding of family. Growing up with a scorpion, he has a very different concept of what a family is. This could lead to him having a complex relationship with the Weasleys or other surrogate families in the wizarding world. He might be hesitant to accept their love and care at first, but gradually come to realize the value of a real family. Also, his magical development could be more instinctive, like how a scorpion reacts instinctively to threats, Harry might use magic in a more impulsive yet effective way when in danger.
Harry would likely develop a very different personality. He may be more solemn and less prone to the typical teenage angst that the original Harry had. Since he is raised by Death, he might be more in tune with the darker aspects of life and magic from a young age.
Harry would likely become more fearless. Knowing that Death is his guardian, he'd have a sense of security that most others don't. He might take more risks in his battles against the dark forces, like confronting Death Eaters without hesitation.