I weigh 75kg and I ride Futura 111 with 6.0 and 7.4 freerace camless sails. Since you weigh about 82kg (sorry, I have to transform it to SI unit system)
, I would recommend 122l if you are sailing mostly in 15 kts of wind. It would definitely get you planing earlier with that range of sails (probably with 7.0 you'll enjoy the most).
Another thing to consider is the fin.
Most of the time I am using 7.4 sail with a fin 38 or 44. Once winds get stronger (25kts+) I use my 6.0 with fin 32.