You could use a top-down/bottom-up shade and have just one covering. This is your kitchen? It looks like the piece on the right is hung too high, but it's hard to tell from the picture. The center of the piece should be eye level. It looks like you could stand to add some color with the art. Are there colors used elsewhere in adjacent rooms that you could bring in?

I agree with you that the left side needs multiple pieces (or if you find the right thing, one large piece could work). A grouping of four similar in size to the one that is there would work. It is hard to find things you like that are also the right size, so keep looking until you find the right thing, or combination of things. I think the piece on the right needs to somehow relate to the piece(s) on the left as well. Sometimes it's helpful to put up painters tape outlines to help you visualize how pieces will fit.

a inside mount blind, top down/bottom up for light control and privacy.

I would get a large format framed canvas (available anywhere online)

and center it between the wall and window (the Pears are generic kitchen) Centered eye level.

the framed piece on the otherside looks too high, to me. You don't need to put something on every wall just to fill the space, a sinle statement is great.