I see you're starting on G# for some reason. In my particular case, the piano starts off with A and the highest note is C. Since it is clear that not all pianos start off with the same note, it may be best to just stick to the conventional c through b and just make one more octave than the paino would typically have. That would be used to cover any variation in starting and ending keys.
EDIT: doing a little more research, the lowest note on an 88-key piano seems to always be A0 while the highest note seems to always be C8.