bikes are always personal preferance. always.
here are some links to learn more, if you wanna dig. if you just want to take someone's advice as gospel, go right ahead. but this is a decision you need to make, not get it made for you.
I Prefer the EX250 ninja, and a brand new one MSRPs at 2,999. it is the cheapest 250, but buy your 1st one used, you are going to drop it, it might as well be the one you bought used, not the new one. it also gets 55-75MPG. the cruser models are more expensive. Also I am 6'0" tall and wheigh more than you, and this little bikes still achives highway speeds (it maxes between 105-110 with 300lbs on) I rode mine 1600 miles from upstate NY to sothern MO and never once even thought I had "sore-bum-itis". I know you said you don't like sportbikes, but there is some nice info on the ninja250 rider's club FAQs for new riders. and some maintinace how-toos that span beyond the street bike.
and BTW, even the people who like the feel of crusiers give the EX250 high marks. don't just scoff because it's not what you wanna hear. an informed rider is a wise rider.
of all of these bikes(beginner's bike link below) the EX250 is the only one that has been largely unchanged since the late eighties. this means lots of cheap parts when you lay it over. and this bike is by no means a beginner's only bike, as the YouTube video will show.
and the best advice anyone can give, take a motorcycle safety course,the link to find one in your area is below. most motorcycle safety courses use the Ninja to teach you how to ride properly because it is such a cheap bike to fix.