READERS' PICK: Play it cool, boys, just play it cool. Etherton, dean of contemporary art galleries in Tucson, has always struck us as a jazzy place. At the top of the stairs there's that big, New Yorky loftlike space; you can just picture jazz musicians smokily improvising on their horns. Proprietor Terry Etherton fills it, year in year out, not with musicians, but with sterling local and national artists and photographers, none of them content to deliver the merely decorative. Painters Nancy Tokar Miller and Bailey Doogan both had challenging shows last winter, examining place and the body, respectively. A stunning four-person photography show in the spring led the way back to the future, using cumbersome old-time photographic techniques to make cutting-edge art. Etherton's become a bit of an empire builder of late: His holdings include a satellite gallery at Fifth Avenue and Broadway, the Temple Gallery and the gallery in the old Joesler studio at Campbell and River. He's put all of his places, incidentally, in rehabbed historic buildings. More power to him.