Student looking for some board advice.
Hey /r/surfing, I wanted to ask some board advice that considering my situation I felt warranted its own post. I am an intermediate shortboarder, and I mean that as I can surf anything under 11' comfortably, can spot the peak and navigate into the wave well, fall maybe 10% of the time but only recently started doing turns and snaps. I was doing alright on waves up to 4-5' but hadn't tried anything in bigger swell yet as when I broke my board it was the first decent one in awhile.
My board finally gave out on me after having it for 5+ years, it was a garage sale buy and [here are pictures of it post-break.](http://imgur.com/a/zGhBZ) It is not worth repairing whatsoever. It's dims where 6'5" x 19 7/8" x 2.5" and it's the only board I've used in recent times. I learned on a 5'10" shortboard when I was 9 so I guess a gun compared to me then. I'm going the craigslist route, I live in southern California and I'm wondering what I should look for in a board as far as dims/general shape goes.
A few additional things: I am going up to UC Santa Barbara in the fall and will be surfing a lot more frequently both this summer due to my job (lifeguard) and in the school year thanks to the awesome location of the school. I don't know the breaks well but perhaps this could influence what board I decide to get.
Another thing is that I'm very suited for surfing, and this I feel could bring my optimal board's length down considerably. What I mean is I'm a college swimmer whose best races are the 50 and 100 free with times of 21.4 and 46.2 respectively (that's pretty fast). I am extremely comfortable in the ocean as well as the pool and can go for 8-10 hour sessions without a problem. The smallest board I have recently ridden was a 6' T. Patterson (only once) and had no trouble getting waves. I don't know the volume of either the Rat or the T. Patterson though so it's hard to make a good comparison.
I am 20 years old, 6'0 and 165-173lbs (depending on how much I gym) and I am very much in shape and snowboard/longboard decently. I'd like to work my way up to fast cutbacks, snaps and eventually airs/rotations but I know this comes with considerable time and effort (I'm used to it though thanks to swimming which is immensely more boring). Getting barreled is awesome too though.
Based on my athleticism, experience, ambition and location what board size/type do you guys think would suit me? Thanks in advance!