9`2 to 9`6 are perfect lenghths, look at what the pro`s ride
but for sure its up to you how many steps to the nose you are comfortable with, at 85 kg wet and intermediate +30 to 40 ltrs is good so around the 115 ltr mark will be ideal but the offset will be in the width as the board will need to accommodate volume
Style really is an amazing board and is lighter and stronger than others + off course proper shaping pedigree
9′ 6″ x 27 1/2 x 3 7/8 @ 112L
10′ 0″ x 29 x 4 @ 130L
both killer boards that are amazingly agile as a single fin set up
Hope that helps - check the review