Consider things from this point of view.
Vary your Aperature to control DOF, vary your shutter speed to control sense of motion, vary your ISO to control light sensitivity and noise level. Consider using your focal length to control composition/distance from the subject. A properly composed shot will do much much much much more than a shot taken at a specific aperature and focal length to ensure maximum sharpness.
If you want to look at the numbers, photozone.de has the test numbers at various aperatures and focal lengths for sharpness.
But I think the object of photography as an art form (if you are interested in that) is to convey emotions, not a sense of sharpness. A minimum degree of sharpness is required to ensure that softness doesn't distract from the shot, but that is pretty much it. I know for certain areas such as architecture and landscapes that sharpness is important though, but again, I feel that just absolute sharpness is over emphasized.