Rug or no rug [to add color, etc.] maybe a color at the windows?

https://www.groupon.com/deals/gg-cotton-108x84-burnout-grommet-panel-pair

Not sure what color would be right for your home, but here is your dining room with drapery panels and a larger chandelier

So pretty but 84" tall:

https://www.groupon.com/deals/gg-silk-organza-loop-panel-pair

Brown rug with leaves that include it seems an icy aqua, which you could use in curtains... 8 x 11 for $150.

https://www.groupon.com/deals/gg-flowering-branches-scatter-rugs

It's hard to tell your wall color on my monitor because your photo is too dark but I agree with purchasing beautiful drapes with some pattern and getting a larger chandelier. You do not need any art.

Here is a drapery concept that could be considered for this uniquely configured room. Install drapery rods at the top of all three walls and hang fabric panels continuously around the room.