I'm really not sure what you are trying to do or duplicate. If you are trying to pick a frame size before you buy, then best of luck to you. I try them out first. But there are websites that can let you compare bike geometries in a visual way and see one image superimposed on the other. I've played with one years ago, but it wasn't all the help I expected it to be. And I had to put in all the exacting measurements for each frame.

As for saddle setback, I don't try to base that on the other bikes, I just ride the bike and move it till it's where I want it. If when I pedal hard I slide too far forward in an unintended way, then I try to decide if that's the dynamic forces of pedaling trying to keep me in the right relation to the BB or if my reach is off. Might be tilt for some if they angle their saddles, I keep my saddle pretty level.