I've found that setback is over rated. Typically issues people try to solve with setback corrections are directly related to a saddle that's too high.

Also the last thing cycling needs is another useless formula...

When you have your saddle height set, push around 90% VO2MAX or at FTP for five to ten minutes. If you feel strain mostly in the quads, move saddle back. If you feel strain mostly in the hamstring area or back of the leg, move saddle forward.

It's actually easier to start out with the saddle pushed back as far as it'll go. That way you'll start noticing the balanced strain between quads and hamstrings and you'll notice when you'll start getting unstable / falling forward. But with the correct (low enough) saddle height people can handle quite a large spread of setback positions.

The prerequisites for all of that to work is a saddle that's stable for you at your chosen pelvic angle and not too much reach. Funnily enough too much reach (which is also really common) causes same sorts of issues as too much saddle height.