I applaud your care and precision! One question about the saddle setback: you measured saddle tip to a plumb line aimed at the BB center and the TIPS are the same distance behind. But the distance from saddle tip to where your weight is supported might not be the same if the saddles are not the same model and perhaps the same year. I use the widest point of the saddle as the location for my sitbones. At least based on sticking my fingers under my butt when pedaling comfortably, I think ... that's a decent indication. One may ague the point, but its quite clear if you look at them, a broken-in Brooks Swallow, a brand-new Brooks Pro (or B17), a Selle Anatomica which has stopped stretching, and a Specialized Toupe will have different distances from saddle front tip to the center of rider pressure. In part it's geometric distortion due to extensive loading with rider weight. The Swallow and the Selle AnAtomica are commonly seen with elongated noses and tension screws nearly "all done," where Professionals, B17s, and Toupes change relatively little. I tend to measure from saddle rear tip forward or saddle center along the line connecting the sitbone center of contact.