Leaf shape is definately another good indicator. Short, fat blades are usually indica heavy and usually limited to 3-5-7 majority, and longer, skinnier leaves are usually Sativa heavy. I grew a few Sativas last year and some of the fan leaves had fingers that were 8" long, and most were 7-11 blades. They absolutely dwarved my hands.its more a GSC shape
afghan genetics(indica) have tendancy to display 3 fingers leaves, it's normal