The chairs are a good match. Leather is probably best, great for kids' spills and accidents, but any fabric will do. Not sure on purple with green - those two colours together clash a bit for me. The green kitchen looks great, and I'm a fan of dark wood. The only thing throwing it off at the moment is the yellowish coloured walls. If they were repainted a soft white, this would make the green and the dark wood really pop, giving you a fresh and sophisticated, calm look which I think would work well. You could then upholster in a green to match the kitchen which would look appealing. Finish it off by some fresh white flowers as accents in the room to draw the eye and you've got a beautifully transformed space with a fabulous feature dining area :)

I would wait for the rug, until you have the shutters up and your furniture placed..it may take on a character of its own and you'll want to compliment. My first thought though was to coordinate with your kitchen and incorporate some black, with a black/beige stripped rug, which would be fun with the wallpaper and perhaps paint your chairs black, add the shutters and you could paint the window trim black and add a large black chandelier.

I would get a better chandalier with better lighting and IMO DRs do not have to be bright as they are mostly used in the evening.

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