The there are many, many lovely pictures of Ariel on the web, but this is most beautiful example I have yet seen. Your drawing depicts Ariel quite realistically in the proportions of her facial and body features, particularly her eyes, while still unquestionably preserving her identity from the movie. She is instantly recognizable as "Ariel."
Beyond basic appearances, I love the thoughtful and almost serene expression that you have captured in her, and wonder if this picture captures Ariel at some time during her "second" day with Eric, or if it happens some time later after they have been reunited.
Normally, Ariel is something of a "manic pixie girl," at least in her second day ashore, but the movie and series show that she can be solitary and contemplative, particularly in her grotto. These sort of insights into her intellect and inner emotional life portray her true, spiritual beauty, and in the moment depicted, she seems to have been thinking deeply about something before when something catches her attention. I wonder, “What was she thinking about?”..."What just captured her attention?"