Brickwork is spammy, ceiling is awkwardly low, colors are repetitive, and the ceiling is just kinda slapped on.
Add a crown molding, and raise the ceiling. Change the color of the couches and maybe get a lighter shade of brown for the wood. You've utilized a grand total of 3 colors in the build and it's pretty damn awkward looking, not to mention that shade of green is really gross and dull.
Also the use of prop picture frames is undesirable and pretty out of place, there's other ways to clutter / detail the build.