M mode is my default setting.
Actually I do not want to spend time to think whether I must shoot in Av, M, Tv, P etc.
M mode can satisfy my need most of the time.
After all, changing the speed and aperture in 7D is quite fast. just turn the main and quick dial left and right. to change the focus point, just turn the joystick left, right, up, and down.
Like playing the computer games, if we get used to the button of the keyboard/joystick, we can react very fast.
I get used with the M mode already.