If you had the time and access to the information, you could look at the stats from the IPF for the various female lifters. You could easily find their body weights, but their heights might be harder to pin down. That would give you a rough estimation of how tall the successful competitors are in the various weight classes and you might be able to tease out a generalized number of pounds-per-inch-of-height relationship. Of course, what applies to them may not apply to other trainees. The variables that affect this question rapidly approach infinity. Unless a trainee is significantly overweight, putting on body weight will generally make getting stronger an easier process. What is the ideal weight for maximal strength? For many trainees, both male and female, the answer is, "More than the trainee weighs at present." The usual caveats and exceptions apply. That's all I got.