sunseeker said...I seem to be riding a board about 5 litres too little - no wonder I get sore arms...

Sunseeker, an extra inch will make all the difference. Your 6'2 will always slide as soon as it gets over over shoulder height. I am around 83kgs also and have a couple of 6'3s.
an extra inch on your lenth will let you draw your turns out a little longer whilst giving you a slightly higher "top speed" allowing you drive , rather than slide when its around head height. Keep the same width and thickness . You'll get used to it
after a couple of deacent hacks.
Almost all of my boards are rounded pins, they just seem to drive the line easier while still being nice and loose with a bit of single double

Best of luck ...........