Not sure if you told us where you are going to be commuting, what kind of road, distance, part of the country, etc. 40 miles in rural Michigan on a GS might be sweet, while 20 miles lanesplitting in SoCal a GS might be a handful.
But being 6'4" that does tend to thin the herd. A lot of tall guys lean towards the KTM. But if your knees are healthy, there's really a lot of bikes you could look at. I think if it was my FIRST adventure bike, or my first non-Harley, and my knees were OK, I might be looking at a used V-Strom DL650 (the Wee-Strom). Cheap to buy, cheap on gas, fairly nimble in traffic, ABS brakes for traffic panic stops, can carry your camping gear OK, cheap maintenance, lots and lots of aftermarket parts and pieces to personalize it with, and since you WILL be crashing it out in the backcountry on those camping trips -- cheap repairs.
Then, after the first year or so is under your belt, then go looking at GS's or Tenere's or whatever.
's a link to the Wee-Strom thread index if you want to see what others have to say..