I would recommend for you the new 87. I am 80kg and for 2013 I'm going to most likely register 87, 97, 110 (or 117; haven't quite tested that out yet) for the PWA next year.
Normally I'd say the 97 is a good gap and nice combo with the 110 but if you are comfortable using the 110 up and above 20 knots, then I think you could skip it and jump straight down on to the 87 which is perfect for 7.0 / 6.3 (or smaller) and being that bit smaller and narrower than the 97 you can get the best GPS speeds out of it. I used the 80 in 2012 in anything above 20 knots; they are suprisingly buoyant and plane early so I wouldn't worry about the big gap between it and the 110.
I ordered my 87 in carbon, but I haven't tried the wood version. If it's mostly choppy where you sail, the wood construction usually is a bit softer under your feet and more comfortable. Remi could suggest on the wood vs carbon a bit more as he would have tried them both :-)
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