i would look for a square piece of artwork for the space where the 2 pics are now. Art is something you will have to pick out because it's more personal. As for the buddha, i love it. Maybe just use the gold mirror in another room. May work well above a dresser in a bedroom or above a vanity in a bathroom>
maybe add some silk drapery panels on each side of your shuttered window in the dining room as well.

and, not sure if it would fit, but you may be able to put a nice green plant with a beautiful pot, in the dining room where the 2 pics are living now......also another one in the living room.

maybe make a gallery wall with 5 - 10 unmatched frames, all different sizes, all painted white (or whatever color of choice), containing nothing. You chandelier is absolutely stunning, so I don't think you need much here, but agree what you have there now doesn't quite click in. If not a gallery, some largish artwork that isn't very busy, like a simple ombre-type thing.

Your dining room looks great! All you need is a piece of art.
Here are a couple of ideas( May not be your style). You could go for just I piece of art or put more than one piece here.

I also meant to say,have you tried the mirror that's in your hall in that area,(which I think is pretty glamorous) but try hanging it landscaped instead of portrait . it might be worth a try. It may be too big but at the least you will know if a mirror will work for you in that area.