Call it Millennium Art and Design, the new 21st-century style that is known for its pronounced sculptural sensibilities. Now, design dynamo Wendell Castle (b. 1932) is kicking it up a notch with his current exhibition at Barry Friedman Ltd. in Manhattan’s Chelsea art district with furniture that wins kudos as dynamic and brilliant. In terms of artistry, his new work in fiberglass, stack-laminated wood, stainless steel and aluminum can stand right alongside the high-tech Jeff Koons sculptures on the roof of the Metropolitan Museum of Art. Castle pushes past the routine organic vocabulary to ply a far more refined interpretation of biomorphic forms and as a result masters a kind of softened monumentality. There’s nothing banal or excessive about these pieces.