How about moving the credenza to the left and putting a garden stool to the right of it, with the plant on top of it.

put a chair on either side,,,or chair on one size and that palm plant up on a plant stand. then it will look fine. if just sitting there alone, it's too small.

I think the size is fine I would pull the other armchair and place it on the other side of the buffet, helping to create a more balanced and purposeful look. Maybe think about placing the plant in a different spot in your home.

I would set the palm on the floor left of the piece and add a chair on the right. Colorful art would draw the eye up better than the macrame does. It is a little bland.

I agree with above comments about flanking the sideboard with two chairs.

However, the chairs are likely, what, 18inD? So, if you do that you're losing space that you say you don't have room to lose.

But I bet that you can find a sideboard that's wider, but maybe 12 to 15 inches deep ... so, shallower than the chairs, but deep enough to actually function as a sideboard. Can you even set a dinner plate on that 11in deep one you have now?