Also, thought on adding flower boxes on lower left windows?

Shutters will not fit on the second floor window. There is no space between the eaves and the top of the window. Shutters on the lower windows will look odd without shutters on the top window. I'd paint the window trim a color with a higher contrast, like a white to make them stand out more.

Flower boxes are a pain to keep looking good. You have a garden bed under those windows, that's where your plants should go.