And here's the first draft of the character, based solely off of those sketches.
Quay is a young Skyloftian who has yet to come of age and be paired with a loftwing. This hasn't prevented him from finding his own way, though! With a little help from Gondo and his technical expertise, Quay has managed to salvage and reengineer some of the ancient Hylian technology to create his own Skywing to soar among the clouds! He now holds claim to the Fastest in the Sky... and it's up to Link to try and take that title from him in a racing minigame.
I got the idea from a Miyamoto interview, in which he was asked what sort of things were cut from Skyward Sword. One of the ideas was a racing minigame, where players would either race around a course or with other NPCs like Quay here. However, they were unable to give the loftwings a proper sense of speed without drastic changes, and thus cut the minigame from the final game. I have envisioned who that NPC might have been had that minigame been implemented, and will be taking this character through polishing to 3DS Max for modeling and Zbrush for fine tuning and learning the program.