While a bigger sail will get you plaing earlier & blasting more often, your skills will definitely improve faster with a smaller sail. I would suggest you spend the bulk of your money on a good mast & boom and get used sails until you develop a taste for the type of sail that you like. Many 6.5 sails rig on both 430 & 460 masts so get a good 460, 75% carbon and shop around for used sails. I have a 430 & 460 that are over 10 years old and have been through many sails in that time. If you shop around, some brands have 8+ sail sizes for a 460 mast as well. My 2012 Naish Indy 8.2 rigs on a 460.