I find that artists tend to struggle with doing fan art well - emulating someone else's work is no mean feat, especially when it's work coming from the pros. So sometimes the character will merely resemble that of the officially drawn version due to the artist missing details that make up a character's unique look. Yours, however, looks like it's the official version! Bit of a body switch, but you made it work. Kudos!

My favorite Ghibli movie, and you made her so sexy.