The space lends itself to a round table, which offers a great deal of flexibility in terms of seating. I like round tables in casual dining areas. I have a 42-inch round and it's too small for 5 people. I recommend at least a 60-inch. You generally want to clear 4 feet around it, which you would accomplish given the dimensions of the actual room. Maybe a mock-up or tape it off to try out a size.

Your dining area and furnishings are not ornate enough to support a crystal chandelier. Select a multi light chandelier with fabric shades, paint the walls and select some color coordinated drapery panels.

I’m not a pro, but I think one of the best things about a tulip table is how many chair options you have. I can picture it with most of these. (I’m not as sold on the more ornate traditional chairs with it, but I am probably just lacking imagination!)

I don't know your style but this would be a good place for a bench that the style is more unexpected. You could also add a colorful cushion if you wanted some punch of color. Because of the window and the door I'd probably stay with a backless bench for less busyness. Don't know your size needed but just to give you some food for thought below. As far as a rug. Take blue painters tape and tape it on the floor to give you a sense of size needed and if you like the shape. I'd get the bench first as that could change your feelings as far as a rug shape and pattern.