Ciao Luca, the Gecko is a good board for you to progress on for sure. If you think you can manage to stay upwind with a daggerboard, then for sure a smaller board than our Gecko 156 Daggerboard or Vipers is a good choice. Considering your weight, I don´t think a bigger board than the 135 is necessary - it is fairly wide at 79cm(2019 133 is 78cm, also good choice). So I would go with the 133, good luck with progressing and enjoy it!