Sab,
There are plenty of good hairline docs around. Ron Shapiro is problably the best known hairline Doctor, but I also recommend my doctor, Dr. Sharon Keene. Keep in mind that if you are only going to get hairline work, study the doctor's results carefully. Each doctor has his/her own characteristics, which are particularly noticable in the hairline. The differences might be subtle, but they are real. In my case, Dr. Keene did an excellent job in hairline placement and framing my face. In fact, I looked at that ratio you talk about. It is spot on with me. Some doctors are really conservative and will not deviate from their conservative hairlines.