Hey Timmy, looks like your off to a fine start on this one(osage?). Looking at things as if I was working on it....I think the left limb is bending more than the right. left limb has more reflex in unstrung pic and then is lower when pulled on tree. only by an inch or so each way. That said I do like the profile of it when strung at this point. Looks to me like the right limb has some character to it so that makes it hard for me to judge just where it might be stiff. Looks like out of the fade, but then mid limb may be bending more than the left limb is.
I'd use a tillering gizmo. Get things bending even or confirm they already are(even if what I stated above is wrong this will not lie). You could also slowly work towards the outer limbs using it and thus have more limb working for you before you get to bracing it.After brace i'd continue to use gizmo out to 20" maybe more. also watching for even side to side thickness as I go. Check, 10-15 scrapes on stiff spots, exercise wood, repeat. If I feel its bending even but feel I start to stress limbs I know I need more working limb. That's what I think and how id work on it if it was mine.
From what I can see it does look like a neat piece of wood and your well on your way. Hope you find this helpful. Good luck! Mike