Band Over Bypass
I've seen a couple of people who did very well with this procedure---but they're only 3-4 years out. I would really hesitate about adding all the possible complications of a Band. The Band has a limited lifespan of about ten years, so---what happens when it has to come out?
At this point, I urge you to research having your RNY revised to a Duodenal Switch. This is a very complicated surgery, and only a handful of surgeons perform it, so most people have to travel in order to get it. The DS is the form of WLS with the very best long-term, maintained weight-loss stats, and the best stats for resolving or preventing diabetes and high cholesterol.