I think that higher levels = find stuff more often is enough of an advantage. If it gets to the point where you know that you\'ll find something nine out of ten tries, then that\'s good enough without extra benifets.
Not being able to mine twice in the same place might be there to fight bots, but I\'m not sure.
What I ~do~ know however is that once crafting is in the game, then mining will be completely different. All that ore will actually have a price on it, and if you\'re able to supply crafters with a steady supply of what they\'re looking for than you\'ll be in a good position.