Two matching mini-chandeliers could work, but you have a vent and other holes in the ceiling and would have to work around them. If you can enclose a couple of the holes, you could place each small chandelier an equal distance from the center of the ceiling as it corresponds to the center of the table. I would suggest a large, square framed mirror over the fireplace and a large tapestry or other form of wall art on the back wall. By having two chandeliers, the wall art could be seen between them instead of being blocked by a single light fixture.There is a lot of plain space, and white-painted bead board wainscoting could break up the large, plain space and bring a different texture and color to the room. A solid-color area rug inspired by a color in the wall art or tapestry could help tie the color scheme together.