Yeah, the Vyvanse is definitely doing more than just giving me energy and determination. I tried playing the piano on Ritalin, which I was trying out a prescription for earlier, and noticed that the tedium of practice was easier to endure.
Yesterday night and this morning I tried playing the piano again, for the first time on Vyvanse, and it seems that it improves left/right hand independence and the general rate of learning. I'm making fewer mistakes.