A smaller board for bigger conditions?

[Lindbergh]

I enjoy this GO 170 with a 7.5 and 6.5 sail, but feel the chops are limiting my sailing when the wind gets more than 18-19 knots. The board ask to go fast while the larger chops makes the board feeling big, and sometimes I can plane the direction the waves go, but not the other. I have found a flat water spot, but the wind have to be below 18-19 knots to blast comfortable there, and the coniditons are not allways right. When the wind picks up, the chops and my board starts to fight. I can plane in both straps when in realative flat water on my 56 cm drake fin.

To increase my TOW, I would like to sail in 15-25 knots and chops up to about 1 meter, but not sure if I should do it with the GO 170. A couple of weeks ago, I tried a fanatic shark 130, got in both straps easily and felt it was much less sensitive to chops while planing. I was also surprised how easy it was to sail that "small" board, so a thank to GO 170 for learning me the tricks!! Now I am pondering about adding a smaller board for the windier days out in the ocean. I also know it is possible to add a smaller fin to the GO 170, but from reading articles, I understand it is easier to go for a smaller board.

My question: to sail in chops 50-100 cm, with 15-25 knots winds, what size/kind of board do you recommend for me? My weight is 86 kg.

My second question: how does those formula guys plane in big chops and 25 knots of wind with big sails and fins? Is it due to the formula boards beeing shorter?