I have a Vulcan 500 and would highly recommend it. If you want to go with a cruiser, in my mind, it’s a great bike for a new rider in that it is not so large or heavy that it’s hard to control or learn on, but at the same time, it has plenty of power that you won’t outgrow it as quickly as you would a 250 cruiser. Freeway power is no problem. It also probably has the most comfortable stock seat of any of the smaller cruiser. My wife had no problems riding my Vulcan, and this was after she had only been riding for a week. In fact, she commented how much smoother it was to ride than her 250 cruiser.
If you look at various reviews of the 500, it’s hard to find anything negative about them. I usually get around 55-58 mpg on it. My only concern would be leg room with you being 6’2″ (I’m 5’10”), but I’m not sure that it wouldn’t be a problem on the Ninja either. Just find one at the dealership and sit on it to see what you think. I don’t think you’ll be dissapointed if you go with the Vulcan. Good luck with whatever you choose!