A long-form series has the potential to slow things down and let us actually watch characters grow in ways that feel more natural, and I really hope the TV series gets it right.

The house dynamic is especially interesting in that regard. In the books, the houses already have more nuance than the films showed, but there's still plenty of room to explore how those traits evolve. The show could really dig into how characters wrestle with how ambition, courage, intellect, and loyalty can manifest in different ways depending on the situation. This, though, would depend on whether the story is told from a perspective that is strictly restricted to Harry's experience or if it will explore beyond that.

I'd personally love to see more balance. Slytherin, for example, has always had the potential to be explored beyond the "villain" role, and a series format could highlight ambition, leadership, and resilience without automatically tying them to villainy. Likewise, Hufflepuffs and Ravenclaws could get far more narrative attention and showcase their strengths, flaws, and conflicts instead of being reduced to the background until needed for the plot to progress.