Replace the yellow throw with something with stronger, warmer colours.

Replace the lamp with something warmer and more ornate... Oldschool brass ornate thing could be cool to find.

Replace coffee table with something made out of wood.. Turned legs or something is nice.

Find some things to hang.. A mix of stuff is nice for cosiness.. Framed pics, hanging sculptures. Maybe look at a shelf above the couch, offset to one side for Nick nacks and cool stuff, then balance visually with hanging art.

A plant to the right of the TV.. Or if you don't want to take on something that needs tending, just find an interesting looking branch of the right size, clean it up and lean it up there, maybe with some things hanging from it like little string lights.

A dark rug incorporating your favourite colours under the coffee table.