Macro shots and limited depth-of-field...

Is this a true statement for macro shots?

TO INCREASE DEPTH-OF-FIELD (DOF)
Move the camera further away from the object (drawback? smaller image)
Decrease the aperture (say f/22) (drawback? slow shutter speeds)

I love macro shots, but I often wish for more depth of field from my 90mm macro lens (yes my expectations are realistic.) I could live with a smaller image if it gave me greater DOF.