My situation was very similar to yours during this past riding season Mark. A number of years since riding regularly on a much smaller bike, recent completion of an MSF course, a regular bicycle rider, and I'm 6'1" and 235 lbs.
I don't think you'll have any trouble getting used to the extra weight and power, as long as you build up your skill sets before "pushing the envelope". I have a 1980 GL1100i and found it to be very well balanced, even in low speed maneuvers.
I'd heartily recommend reading "Maximum Control - Mastering Your Heavyweight Bike" by Pat Hahn. It reinforces some of the material presented in the MSF course, but has a lot more practical "real world" stuff that makes a lot of sense. I found myself reading a passage, then applying the info during my next ride (usually with success). Great book. Welcome to CGW! John