I can speak for the Vulcan 900 (Classic in my case). I own a 2010 Vulcan and absolutely love it. Then again, I upgraded from a Virago 250. I am 6' and the Vulcan offers me plenty of room. I believe the seat height is fairly low so shorter riders would be comfortable on it as well. I don't do 2-ups as my g/f isn't into riding. When riding solo, the Vulcan can easily do 120 kph withouth whinning. However, I do at times look for that unavailable/imaginary 6th gear. I like the slow speed maneuverability of the Vulcan and love the "gauranteed neutral finder". When the bike is stationary and in first gear, you will NEVER miss neutral if looking for it. Thats the Kawasaki's guaranteed neutral finder. I also like the fact that it has a fuel guage, although, its not very accurate. Having said that, it errs on the side of caution; when the fuel light lights up, you still have about a quarter of a tank.
If you do decide to get the Vulcan, the one thing you will need to get used to is the famous Vulcan "tick".
Hope this helps.