Do you like dining rooms that are more formal, or more casual? I lean more casual, although, as a spectator, I can admire beautifully appointed, fancy dining rooms. But me, I always need more weathered woods, and softness, sometimes whimsy.
This antique French gateleg table below is my ideal. I have an old one I got in New Orleans, that is acting as a side table for now, but someday I want it to be the main table again!

Really like most of this dining room-- that table, the vintage chairs and mirror, simple stoneware pitcher and frosted glass candle sticks, the horse, sweet polka dot window treatment. But I think a darker stained floor would set the whole thing off better than the light finish they have, which doesn't quite work for me in this particular neutral room-- more contrast is needed--
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.... a floor as lustrous and rich as this one below, would suit both casually appealing rooms.
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To me, part of what makes dining rooms "informal", is when the different elements -- sideboard, table-- don't necessarily match. I like the eclectic mix here. It just seems "relaxed". But then I enjoy the combination of both painted, and natural stained furniture.
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This is moving toward a little more formality below, with the symmetry of the china cabinets and the sconces, but the softness of the generous curtains and the painted chairs, the bohemian quality of the bamboo blinds, the gentle natural light coming through, keeps it approachable.
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To me, Steven Gambrel is great with dining rooms-- they can be stately, yet feel friendly too. I think he achieves that with the next two. This one says, "come right in" --
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.... and in this architecturally spectacular room below, he purposes an intimate dining area that takes advantage of the curving window to give diners a hospitable round table, and a cushioned window seat to loll on...
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Maybe this room below is closest to being textbook 'formal', with its sparkling chandelier, fine wood, and matching wall and apricot silky curtains? But, there's no stiffness-- it still seems inviting. And that banquette visible in the distance on the lower left-- can't you see some guests just drifting over there to continue conversation and after-dinner coffee...
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What are your must-haves, or on your wish list, for a dining room?