It's hard to tell from the pictures, is the leather furniture a couch and loveseat?

Looks like the perfect spot for your Christmas tree.

Add some window treatments, like roman shades, then the space will look more finished. Because you already have blinds, you can do faux romans. Or a nice valance. Regardless, you need window treatments and because you have no stack back on either side, a faux roman shade or a valance that is hung several inches above the window casing so that only the top 6 inches or so of the window are covered will work well on the windows as they sit low on the wall. You can also add a small upholstered bench along the wall to the left of the left window.

Try angling the chair and ottoman in the corner, oriented towards the sofa and loveseat. It will make the seating arrangement more conversational, as arcy_gw notes. A small end table for a cup of tea or a book should complete the corner nicely.

I'm glad the chair in the corner worked out well! For Roman shades, I'd look to a milky white. Like below:

My preference would be to mount them outside the frame and to the ceiling, to allow as much natural light to enter as possible. When they're open, the bottom will just cover the top of the frame. However, your mantel may be to close to the window frame for that treatment (?)