What a difference a little straightening up makes. The Metropolitan Museum’s New Galleries for 19th- and Early 20th-Century European Paintings and Sculpture have reopened, with new lighting, new architectural trim, a certain re-shuffling of artworks — and a whole new series of galleries on the south side. The results are impressive, with a more intelligible arrangement of artistic movements and many works displayed to better advantage. There’s also a number of never-before-seen works tucked among the regulars.

With the addition of the Henry J. Heinz II Galleries, the total space has grown an additional 8,000 square feet, increasing the total floor area by about a third. The new galleries blend with the old in surprisingly seamless fashion. (If you didn’t think that exhibition space could be made out of thin air, run down to the first floor. There you’ll see the underside of the Heinz Galleries, cantilevering across the upper section of the vast Gallery for Melanesian Art.)

All the rooms, moreover, have been renovated in a more classical style. Gone are the modern walls — the unbroken, floor-to-ceiling expanses — of some of the old galleries. Except in the rooms for 20th-century art, every wall now has 3-foot-tall wainscoting, painted in warm, muted hues matching the door trim. Walls are variously a pale Naples yellow, a grayish mauve, or a deep terra-cotta hue. These touches make the new galleries distinctly more sumptuous, but this is only in keeping with what the artists themselves would have expected in their day. It also suits their paintings’ ornate gold frames. A different attitude to the hanging is evident, too, with paintings snuggled slightly closer to each other, and large works occasionally placed tightly between doorways. The effect is quite pleasing: After being treated like auras, the paintings are now objects, which is no disadvantage for artworks able to speak for themselves.

Approaching the new galleries from the grand staircase, one first glimpses, several chambers away, an American painting: Sargent’s portrait of Madame Pierre Gautreau (1883–84). But this is definitely the right place: The Cantor Sculpture Gallery opens up onto the familiar assortment of work by Rodin, Puvis de Chavannes, and French academic painters, and, thanks to the removal of some pillars and the reduction of display cases, they occupy a much airier space. To the left, the small Havemeyer Galleries with the Degas pastels and sculptures have generally the same “hang,” as do the André Meyer Galleries next door with their Ingres and Delacroixs. (The Turners, however, are momentarily out on loan.) In the gallery beyond, Corot has a room to himself, with some new small landscape sketches mixed among the usual gems.

At this point one enters the first of the new Heinz Galleries. Here they consist of several small chambers of mostly 19th -century outdoor sketches by painters of various European nationalities, all hung very closely together. (Roman ruins are a favorite subject, reflecting the customary training of the time.) Caspar David Friedrich and his associates fill one intimate gallery, and Daumier and Millet share another.

Visitors proceeding directly through the middle galleries from the Cantor hallway will find that large canvases by Manet and Degas continue to dominate the large central room with columned archways. One notable change is Courbet’s eviction from the first small chamber, splitting up what was surely the oddest couple on the floor: the pairing of the arrogant, boastful Courbet (a superb colorist, and no mean draftsman) with the fussy Franz Xavier Winterhalter (whose weightless colors only underscore his meaningless gestures.) The academic painters Bouguereau and Cabanel have moved in, and they are far better roommates for Winterhalter.

Beyond Manet lies a roomful of Americans who spent much time in Europe: Whistler, Eakins, and Sargent, with his afore-seen “Madame Pierre Gautreau.” To one side, occupying a fair-sized niche of its own, is the new Wisteria Dining Room, an exquisitely intact Art Nouveau interior with pointillist landscapes surrounded by carved walnut panels. Elaborate lamps and hardware complete the exotic effect. Straight ahead in the new addition lies a large gallery devoted to Courbet, where visitors can absorb the recently cleaned “Young Ladies of the Village” (1851–52). Many of the works by this master are currently out on loan, and the largest wall has been temporarily given to Rosa Bonheur’s huge “Horse Fair” (1853–55), which benefits greatly from the long sight lines. Directly to the right lies a room of fin-de-siècle art: lacy, anxious paintings by Boldini and Sargent, plus three colorful canvases by Sorolla, including the just-cleaned “The Bath, Jávea” (1905). On view for the first time is Henry Lerolle’s large “The Organ Rehearsal” (undated), a startling, if rather wooden, image of figures silhouetted against the illuminated interior of a church.

With their wealth of Impressionist and Post-Impressionist paintings, the nine rooms of the Annenberg Galleries at the right end of the Cantor hallway will continue to be the first stop for many visitors. The grayish-mauve walls of the Monet room lend an especially vibrant air to his portrait of the façade of the Rouen Cathedral. A few galleries away, the walls of Cézanne’s room, sporting the same color, bring out the rich variety of medium-dark hues in his monumental rendering of his wife.

Beyond the Annenberg galleries lies one of the most pleasant surprises of all: three galleries of early 20th-century works that used to hang downstairs in the Lila Acheson Wallace Wing. Now two walls of first-rate Picassos, centered by the portrait of Gertrude Stein, stare across at equally vigorous Matisses and Derains. A room of Symbolist work does seem like a destination for leftovers — British painters William Nicholson and Duncan Grant seem ill at ease with Redon, Klimt, and Ensor — but the adjacent gallery dedicated to Bonnard and Vuillard is a delight. Their canvases fit comfortably in their new, smaller space — they are intimiste painters, after all — and among them hangs a new, sparkling Bonnard still life. Or did it simply not stand out when it was hanging downstairs? In any event, this exuberant painting seems to be settling right in on the second floor.

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