I think that the "I-40" in your subject line tells the most. I've never owned a Harley, but I've had a Honda Shadow and a Valkyrie Interstate before the C14. Without a doubt I can say that the Kawasaki is my favorite. I love it for the power, handling, excitement, but NOT for the comfort. If you read these forums very long, possibly the most threads are about trying to make this thing comfortable. It's not. You've got the seat debate, the handlebar debate, the grip debate, the windshield debate, and on and on.
Now, with my custom seat, my Murph's risers, my Phil's (now Murph's) wedges, and my custom angled handlebars, the Concours is STILL the least comfortable of the three most recent bikes. I'm still dreaming of highway pegs, and sometimes I wish I had lowered footpegs (but not in the twisties!).
My favorite riding is backroads and two lane state roads. My least favorite riding is superslab. From what I read here, that's a pretty common attitude. Even when I am going a long way, I find myself looking for parallel roads that I can take to get off the freeway for a couple of hours here and there.
So I think that your count probably reflects the strengths and weaknesses of the cruiser platform, as compared to sport touring bikes in particular. Those cruisers are right in their sweet spot. Steady speeds in straight lines. The reason you did not see more ST bikes is because you were on I-40 instead of US-60, or "Route 66", or any other of the more interesting roads that run E-W across the country.