My main hammer is a 4 pound double face similar to the pictured hammer. I vary the weight by moving up and down on the handle. I choke up for lighter blows and use more handle for heavier blows. Works well for me. I use it for most everything.
My anvil, a Trenton 200 lb, is on the soft side so I always soften a new hammer by drawing the colors with a torch. Much better to have to dress a hammer now and then than to ding up your anvil when drawing a thin taper.