Respectfully disagree. A 71 would be a PITA with an 8.0
Depending on whether you want to spend more time in reaching zoom zoom or VMG mode, Anything from 83cm to a used iq board may work for you. At the skinny side, it will depend on the combination of width, tail width and volume as how comfortable an 8.0 will be. My AHD 83 carries an 8.0 easily. My JP 135 while slightly wider overall has less tail width and volume so an 8.0 is much less fun.
An iq will definitely be bigger and bulkier but if you can grab one used at a reasonable price, they can be good touring boards from 6-20+ kts. If you are going new, a lot of good boards in 83-86 that will suit you plus a number of used boards like JP 135, Fanatic Stingray 140, Starboard 150, RRD H-fire 91 (not the race one) etc.
btw, don't dismiss cammed sails out of hand at some point down the road. There's a reason most of us use them in the larger sizes. They'll give you a lot of range and let you stay out on your gear when you could easily be down 2.5-3m2 but are too lazy to go in and rerig.
Match it with a race, freerace or HA freeride foil between (generally) 800-1200 cm2 and you'll have a fun kit for those flat water blasting sessions. Not all foils, though, are created equally so don't compare strictly on area or even aspect ratio. Try to get some feedback or read reviews.
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