Let me start with ...don't be so hard on yourself! You have done a beautiful job ...the dark feel of the room could be easily addressed be re-painting the wall behind the TV as an accent wall..it appears to be the biggest paintable space so will have the biggest impact to bring a little more life and light to the space..if you even took your paint formula and cut the pigment formula in half it would have a huge effect...if a color change is interesting to you stick to colors about half the depth of your other walls..my first thought went toward a pale dusty teal.. One of those indefineable shades...not blue...not green ...sort of a watery shade...if you have a creative painter who can do it an ombré wall could knock it out of the park...start darker at the floor and gradually fade to much lighter at the ceiling...place some up light cans strategically to accentuate the new color

Thank you ritasj for your advice! Changing paint color never crossed my mind!! I can see how it would certainly add interest and life to this room! I will need to find a color specialist to help me find the right teal shade for a feature wall. Is there a Benjamin Moore color you could recommend? Also, would that mean that I would add teal assessories like cushions etc? I don't know what the lighting cans you are referring to are?