An imaging sensor of an imaging reader senses return light from a target to be read by image capture along an imaging axis over a field of view that extends along mutually orthogonal, horizontal and vertical axes. Two aiming light assemblies are offset from the sensor, and direct an aiming light pattern at the target. The pattern has an aiming mark in a central area of the pattern, and a pair of aiming light lines that are collinear along the horizontal axis. The visibility of the aiming mark is enhanced by optically configuring the aiming mark to be different in brightness and/or color and/or size and/or state of existence relative to a remaining area of the pattern. The aiming mark of enhanced visibility constitutes a prominent visual indicator of a center zone of the field of view.