My 7-8 bf board in large swell/chop (freshwater) is predecessor Acid74, but I have about 30+ kilos more. For your weight, a 74 will be too big in more than 6bf. You need 68 if not smaller, don't know your location, maybe some gorge sailors could give advice. I always wondered what do 50 kg sailors use in high winds - customs I suppose.
I would be wary of the very light carbon boards in hairy conditions. There have been comments that new carbon Kodes are a bit clattery, maybe wood is better for control, haven't tried for myself.