I am not light and not tall. I put 56,000 miles on my first R65, when I lived in LA. I commuted on it and I toured on it. It was my first new bike, and I guess I just didn't know any better, that it wasn't for the freeway or touring. I never had a problem with it.
Now I have another one. It's one of 8 BMWs in my stable. I can choose to ride an R90S or an R1200ST, but I have still gone camping and touring on this bike, and enjoyed it.
But you do have to wind it up more than the bigger Airheads, and the top end is around 100mph. There's a couple sections of freeway up here in the bay area where the rain grooves move the tires around some, but I haven't found it really annoying. It's 30 years old, after all, and you can't really expect modern performance from it. Still, it handles well and, ridden up to 8/10ths, it's a joy.