The dark casework helps to balance your dark furnishings. If you were doing anything, replace the dark leather if you want a lighter look . . . before you go at this piecemeal, go look at houzz photos and pull some inspiration rooms that you like . . sometimes we can't see what we want in our space until we look at others.

I wouldn’t paint the built-ins they look like beautiful cherry wood and go really well with the stone on your fireplace. It seems that the room itself just doesn’t get much natural light. replacing the leather sofa and chair with something lighter would help along with a lighter rug. Also, remove the shutters from the two windows that may be blocking some light.

My family room is dark too ,not a lot of natural light but I put in a white shag rug and painted our tongue and grove paneling white It was a hard thing but I love it now.. I have wood floors .. mirrors do wonders too for reflecting the light you have.