If it were me, I would lose more to try to get off the last medication. Health is the most important factor to me. A size 6 or even a size 4 at 5'5" tall, is not too thin. You may think so, but if strangers on the street saw you, they would not think you are too thin or look sickly at that size.
Skin, if not attached to fat, does not weigh much. Also, most people I know who had plastic surgery, even with a slight loss of weight from the skin tend to bounce back to the weight they were before plastics. I would not factor that into the equation.
Laura in Texas
52 years old; 5'7" tall; HW: 339 (BMI=53); GW: 140 CW: 150 (BMI=24)
RNY: 09-17-08 Dr. Garth Davis
brachioplasty: 12-18-09 Dr. Wainwright; lbl/bl: 06-28-11 Dr. LoMonaco
"If what you're doing doesn't work, change what you're doing - don't complain that it doesn't work."