I'm 65 kg and learnt to foil and wing on a Naish crossover 120 which is 7'4, using the jet 1650 and have had an amazing time on it. Incidentally, I'm now waiting for my new smaller board to be delivered so will be selling the crossover, but my thoughts...
I'd potentially interested in your Naish Crossover 120 if you sell. Let me know.
Dave