Golf club heads (e.g. drivers, fairway woods, wood-type hybrid clubs, or the like) according to at least some example aspects of this invention include a striking face and a rear portion opposite the striking face, the rear portion defining an opening to an interior cavity. A rear body member configured to be inserted into the opening is engaged with the rear portion of the club head. The rear body member may include multiple rear body parts that may be removable and/or interchangeable to permit flexibility in controlling the weight distribution of the golf club head.