Allan Langer and Matty Bowen. Alfie just made everything look easy, and the fact that he continued to play at such a high standard all the way to his retirement shows that he is just a natural footballer.
Matty Bowen gets my vote, he is the kind of player who doesn't plan things, nor does he play to any type of plan. When he gets the football, he plays on instinct; he does what comes naturally, and that is why I think he is one of the best, if not the best natural footballer.
A few that other people have said like Mundine, A Walker, Blacklock and Peachey... Something I have noticed in the game, in particular over the past decade or so, is how strong Aboriginal and Torres Strait Islander players are. They seem to possess this brilliant flair in their games, which isn't the typical "technique" in the game, but use a laid back, entertaining style. They also portray a tremendous amount of spacial awareness. It is almost as if nothing is going on, then all of a sudden they've set something up, or it all looks lost in defense and they are there.