Ack, where did my long post go? Sigh, will try to redo it.
Your dining room width will be fine depending on how wide your table is. I have a 9' wide dining room and it works just fine with my 38" wide dining table.
Palimpsest's design is a big improvement -- that fridge location makes much more sense.
I don't think completely enclosing the kitchen with actual doors makes sense. Go for an open doorway on the south wall at least. Not even my Granny's 1956 kitchen had actual closing doors on all sides.
I understand wanting to keep a feeling of separation between the two rooms in order to maintain a formal dining room, and the sliding doors does offer that plus gives you a way to hide the dishes during a dinner party. However, if you were open to dropping them you could put a peninsula in along that opening instead, which would give you more cabinets and counter space. A cased opening can help keep the feeling of separation and formality -- pics below of how we did it in our 110-year-old home.
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corner sink and dishwasher
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