No reason to back hickory, unless it's horribly violated. Hickory is the best backing material, IMHO. Hickory/ipe pyramid bow will easily fulfill your wish list. 1.5 - 1.75" at the fades, tapering to 0.5" tips. For glue up, I use TB3. Make sure your surfaces are flat, perfectly matching, and clean. The contrast of ipe and hickory makes a terrific looking bow.