If you have one formal and one casual dining space, you can really go to town with different chair designs for both. A casual spot will do best with sociable, comfy seating that naturally leads to conversation, whereas a formal setting is where you can play around with luxury fabrics. If you only have one dining room, you're going to need to combine all of these elements in one set of chairs, if possible!
The iron chandeliers hanging from the ceiling add a certain quirkiness in the area that makes it look very modern and unconventional. Here are some more unconventional dining spaces to mesmerize you.