I love the design and I hope you won't get me wrong, but I think you're getting carried away.
The changes you want are more than just a few new skin elements, it's a complete redo of the interface. I'm just not sure it's something that Steven would want to do.
He might, I have no idea, but for now it's seems to me a waste working how it would look in Photoshop when it can't be done in the actual software.
Peaching the idea was good, it's a great design. just hate to see you wasting time keeping the PSD updated when it will probably won't be possible to execute.