Welcome to the wonder that is Kayaking!@!
DEMO!!!!! DEMO DEMO DEMO
Find a local shop, and demand some demoness!
If I were you, I'd be me; and I would seek a knowledgeable person to find a yak that would suites my needs.
You need to ask your self realistically, what will you primarily be doing? Flat water? a mix? or like my self who started out on a rum of the mill rec boat (prodigy 10) in lakes, flat river, then found my self wanting more; more gnarly waves, more awe inspiring hydraulics, more spine tingling drops, more mind numbing wave trains, more respect for the river Gods whom on a whim can put you in your place by placing a chunk of tree in the most mundane line, forcing you to wonder why you challenge the most powerful force on this sphere humans have named Earth in a tub of plastic with a paddle...
A River Runner of some sort sounds like what you need, something to get you where you want to go and some places that you will wish you had never gone.
I own a Pyranha Everest and it is kick in every way shape and form. I am a bit under its weight range but I get great performance with 30 pounds of water, 10 pounds of camping equip, and about 75- 120 pounds of liquid bread (beer). It is a little longer than some yaks and I have found it does fine on flat water, and is sweet on any "rapid"(but this is my opinion) so I'd surmise that you would like the handling of this boat even with some gear given your stats: but for river Gods sake, demo the derrn boat! then demo any other boat you have found to be your fancy because the last thing you want running through your mind in the waves or on the flats is "I wonder if I'd like that other boat better, this boat is...."
Get the picture? Find a reputable shop and bring anything you think you'd ever need for what ever with you. Then paddle the fecal matter out of it, try rolling with it, try just floating in it. Only you in it, then some gear. Get a feel for as many Yaks as you possibly can. Beg, borrow, but don't steal; to try out kayaks. Once you get things narrowed down to a few boats, Ask your self again what are you primarily going to be doing? Because the best white water yak money can buy will do nothing but circles if you stick to flat water...
But DON'T listen to me, Demo DEMO DEMO!!! then draw your own conclusions. All the advise in the world won't mean a thing if YOU don't "feel" the yak...
A good P.D.F. and a helmet are more important in my opinion because a "great" yak or a "shitty" yak will still put you in the same place i.e. swimming err flopping, down a rock strewn rapid is a nerve wracking experience....
muwahahahahah!
Dont listen to anything that I have typed... but this simple command: DEMO GOD DAMNIT!!!