jandersson, that's pretty interesting about the thumb wide 48" 45# lilac bows. But I'm wondering what is their draw length?
I guess a lot depends on what you need for your trade guy's draw. I see you have 44" working limbs total because of the stiff tips. And the reflex right out of the handle is going to make bringing to brace hard to start with.
Just to give you a thickness data point, black birch, which has a similar very high stiffness, runs about 3/8" thick mid limb, on a 2" wide non-lever 64" 40# bow. No backing. I don't know the quality of the 44" working section of yours, so don't know why the backing. Not making any recommendations one way or the other at all in this, just giving you info to add to your cogitations when considering draw length, width and thickness.