I am very impressed with dedication, discipline and your results. You certainly had to become a different person in order to do that I acknowledge you for that.
I would not suggest using BMI to decide on you goal weight. BMI was designed as a macro-cultural metric to guage the overall health of societies and not for individuals. An ideal body weight is a very sticky subject. I think your ideal weight is one where you look and fell good. I have seen people that have overshot their goal weight and they do not look healthy.