As a point of reference, I just completed a white ash selfbow from a stave, that is 69" long between the nocks, draws 62# at 31", thick ringed, and is 1 7/8" wide at the fades. I heated treated in about 2" of reflex, after a lot of work out it had a touch of set now. Here's what I would suggest for your needs. Usea thick ringed stave, straight or with some reflex. Go about 65" long from nock to nock, 7" handle area betwen 1 3/4" fades. To start out, from mid limb, taper to about 5/8" wide 6" from tip, and then to 1/2". Get the tiller going and later slim down the tips.
Dave