Much of this is open to personal preference. What MUST be done is, upon leaving the handle, the dips must be brought into working limb thickness AFTER the flares have reached full width. Other than that, you can pretty much shape things how you like. I like flow in a bow from end to end and I try to help my handle/flare/dip shape work toward that end. I like the handle to flow into working limb such that it's hard to tell where one stops and the other begins. I've made stiff handled bows that range from 9" dip to dip, to 15" dip to dip. Depends on the bow, the material available, my mood, my intentions for it.
This bow is 12" dip to dip...