Lots of thread on this.  That's actually a big budget for a few good brands if you buy gently used.  Definitely demo the Trident 15  given your physical specs.  The new one is very hefty though:

http://www.norcalkayakanglers.com/index.php?topic=73591.0

I love the Trident 13 from a couple years ago, but I am 195# and you might experience a different ride.  Then again, I pack way too much stuff:  two guns, a heavy anchor (cuz I found it), weightbelt, heavy scallop/ab bars, full camelbak and gatorades.  At my max weight, I can feel that I ride a little low and don't glide as nicely as I could on a longer boat.  But it never feels sketchy in surf and swell.  They are excellent kayaks.  There is a new seat on the T15 that might meet you stadium needs.  That high seating can make you feel tippy, especially if you are tall, though.

What did you end up going with?  I'm looking for my first kayak.