HEy Loeffler,
I've seen several original Sierra Miwok bows, and I think they were also made of incense cedar (though I'm not sure). The ones I saw had flat bellies and rounded backs (probably due to the fact they were made from small diameter limbs). Every original one had a three ply sinew string. They also had a very narrow strip of braintanned deerskin that wrapped around and around the loop of the string to protect it from abrasion. They also had the same very narrow strip of braintan that wrapped around the limb, right at the arch of the recurve (I'm assuming to silence the sound of the string slapping against the belly side of the recurve when it was shot). Don't take my post as trying to critique your work...I'm just trying to pass along what I've seen, just in case you were trying to make an exact replica. If you don't care to copy the originals that closely, then you can just ignore everything I just posted.
But that's a sweet looking bow nonetheless, and amazing full draw pic. That thing takes a hell of a bend! Great job!