Hi there, nice words for Andy, could not agree more, excellent coach/teacher!
Indeed, once the wing bug bites, it stays- but it is a great light wind alternative to windsurfing, I still do both and super fun to have more watertime/less frustrations in light winds.
Yes, the "problem" with winging is that for the more talented people drop down very quickly in board size - so you are used to very small windsurfing boards, therefore I would go straight to a 75L which should actually be fine for at least 6-12 months. You should end up riding approx close to your body weight or under - I am 76kg, ride our 75 and 65L Sky Style boards, depending on wind/if it's gusty on a lake etc. So it's up to you, but I am not sure going straight to a 65L/4'9" would work right away, therefore the 75L....85 will also be ok but I think you will outgrow it fairly quickly. 1250 Free foil should be plenty big enough as your light wind foil, or a 1500Aero High Aspect, add then a Free 1000 to have a bigger range. It will take a while still to move under 1000, as it's not a good idea to reduce both board and foil size until you have the pumping technique sorted.
Wings- everyone likes to think they can get away with 1 or 2, which was ok 4yrs ago when we all started, but right now with 3 wings you can cover a massive range of conditions - at your weight you should be fine with 5/4/3 also for the Gorge, of course if you go in typical Gorge conditions you may need smaller? Get the new Duotone Units in standard construction, plenty of power and at your weight you don't really need the Dlab for light winds. Good luck!