Install beams running across the room from the face of the soffit to the opposite side. Eliminate the sconces and add architectural pendants at the center of the room. Paint the entire room in a rich medium tone except for the angled ceiling. Paint this in a pale Blue-Gray. Highlight the trim around the windows flanking the FP in a deeper shade of your wall color. If possible, take up the wall-to-wall rug and replace with an area rug which has an assymetrical design.

Get rid of the blinds ,plant some great landscape out the windows ,install wood wide plank floors , install beam loose the lamps .

I agree with everyone above but would suggest you add some color to the walls leaving the trim and ceiling white.

Change out the wall sconces for something more modern. I would swap the ceiling fan for something dramatic. Also re-clad the fireplace. To draw attention to the height of that wall you bring your fireplace design up the wall, like in the photos below. I don't know what your style is so I sampled a few to show you what I mean about the fireplace.

This one also shows what I mean about the fireplace and light fixture. Adding beams is expensive, if you don't have the budget there are other ways to emphasize the ceiling

I'd create an accent wall on the high pitch gable side. It could be bold or subtle- depends on what you like.

Thanks all for the advice! Any tips on how to properly trim the windows on the right? The space above them is so narrow. And the tv is going to go either above the fireplace or in that space between the sconces. Any advice on that end? I'm leaning towards placing it between the sconces because I don't want to see a black box when it's off, but I hate breaking up the focal points.

In the picture I showed, take a flat piece of trim and fill the space you have above the window all along all four windows, around the sides, and across the bottom. Fill the space between the windows completely. In the end it will look like one large set of windows. Add the narrow piece on top if you like more of a craftsman feel. If the size of the trim along the top is too small with the scale of the windows you can make the edges larger (again look at the picture I posted - the sides are chunkier than the top).