When I was a teenager I "invented" the name Quilla. I thought it was so nifty and beautiful, and a sneaky way to "honour" my author dreams. Now I think it's a little much, a little too purple and magical. Maybe good for a character though.
Quil is from Twilight, right? Or am I imagining things. I think I prefer Quill with the two Ls more, even though it's more wordy. Heck, I kinda like Quill. The Q is fun, and the similarity to Will gives it some familiarity.