I agree with Daniel, one large piece of art would be better. Love your rug, pull it over so that the front legs of the sectional are on it. A larger lamp on the end table would also help.

no no no no! A large colorful velvet Elvis would be perfect (and colorful) just sayin.

move the 2 vertical pieces at the ends down a few inches to match mass with the large central pieces. i think the end piece on the right is too light weight for the corner.

It will look better and balanced if the bottom row of frames are all at the same level. I'd prefer all the pieces share similar frames since the subject matter is so diverse. You need some way to unify it. Placement and frames should do that.

Brooke, can either of the long narrow pieces be hung horizontally? That is the one on far left or the floral on far right?

I like a lot the items you used for your collage (the cow is beautiful!!), but I think there is a lot of empty space between them. Maybe you could rearrange it following decoenthusiaste's suggestions and leaving smaller space between them? I would also try to bring some more red into the room (like the red / orange on the flowers). Maybe with some bright pillows?