A drill bit has cutting elements with multiple cutting surface geometries that are positioned so that their cutting profiles overlap, but do not completely contain or engulf one another. The different cutting surface geometries and the specific overlap create a zone of high density in the middle regions of the cutting profiles and low density in the periphery, resulting in a cutting profile that becomes sharper with increasing wear. Such an arrangement is more effective and stable as the drill bit encounters hard and abrasive formation materials. Moreover, cutting elements with larger axial volumes may be combined with cutting elements having smaller axial volumes.