Fox,, its hard for me to tell in photos,, so I am hesitant to comment, but seems you could get the mids and outers bending a bit more,, that being said,, since you gonna sinew back, you gonna have to re tiller when you see how it reacts on the bow,,
I would sinew back now,, I wouldnt get carried away trying to get alot of reflex,, on your first bow, but if you gently heated on the tiller board backwards so its got a little reflex,, that would be good,, I have strung bows backwards to sinew, and it works but it can crack a bow if too aggressive,, so I suggest a gentle reflex to start,, and with 4 layers of sinew you will hold some reflex,,
ok thats tricky cause every one has a different concept of one layer,, so weigh out your sinew and put about 1000 grains,,,,thats a good happy medium,, like I said there are lots of ways to approach it,, and lots of ways work,, I like the way Laubin describes his method in his book,,but just start and you will find your own way that works that will be a combination of several concepts,,
Marc suggest lightly sanding ,, so do that on the back, I am old school and wash the back and rough it up, but I think either is ok for hickory,, Jim Hamm taught me,, so I still do like he told me,,he would heat to bend using oil,, so washing it was necessary,,
there are lots of ways to do it,, just go with the general consensis,, and youll be ok,, its a forgiving medium,