Good first motorcycle?

I'm looking to get my first motorcycle. I took and passed the MSF course, riding the Suzuki TU250X. Before the class, I had never sat on a motorcycle, so almost no experience. I'm looking for 70's/80's UJM. I like the look of the Honda Nighthawks or the Suzuki CB's, but I'm open to whatever. I'm 6' 3" 235lbs 36" inseam so I want something I can comfortably ride and not look like a bear on a unicycle. Obviously, I want decent reliability (although I realize anything that old will have problems), but I have no problem adjusting valves, cleaning carbs, etc. It would be a commuter first and a toy on weekends. I live in the middle of nowhere, so my commute in 1/2 hour on empty highways. What makes/models would be best in your opinion? What engine size? Anything to avoid?

Added (1). I'm not dead set against cruisers, but I prefer a sportier look.

Added (2). Suzuki GS not CB

A dual sport is the best beginner motorcycle, its capable of almost anything and is by far the safest. Don't think you have to start out on a 250 just because thats what everyone on the internet says. If you have throttle control and self discipline you can start on whatever you want. 250s can get boring quick if you're going to be riding more so for fun rather that commuting. What ever you get make sure its a popular quality bike and is easily resellable, you'll likely go threw many bikes as your 'taste' and ability change.

Do you want to ride the motorcycle, or do you want to drive the cage until you get parts for the old bike?

If you want old school, the Yamaha SR400 is not retro -- it is the same motorcycle that has been built for decades. So old school that it does not have an electrical starter, you must kick it.