Really nice room. Looks comfortable and inviting. Good choice w/new sofas. Like the fireplace as is ... but less clutter could improve the look of it. Not sure what the picture is above the piano. If it is a family photograph, reframe it and the family photo on the mantel with the same frames and put both above the piano. Really like your coffee table. One day it will be a valuable antique if you don't booger it up. So, for the coffee table, consider taking the table to a glass company and having a dark gray tinted thick glass top created for it -- no refinish for the table necessary. (Alternately, cover everything but the top and paint the top only -- perhaps black or else the same white as your cabinets.) Do the same for your current end table as you do for the coffee table. If you're going to add a second end table, since matching the existing one would likely prove difficult, consider a totally different look -- perhaps a wood 2-drawer filing cabinet? http://realsolidoak.com/office.html

Here’s a rug idea. https://www.rugsusa.com/rugsusa/rugs/rugs-usa-freya-abstract-eclipse/Gray/200ECRK29A-P.html And maybe just pick up your wall color for the drapes. What color are your walls, exactly ? On my screen it looks like a sage (?) Also, do you have children in the space? If so, please rethink the glass table. Here’s the rug: Below visual is not exactly true to actual rug colors and texture - but the rough idea: ETA: Art is a very personal thing. Etsy.com is one good resource, for all types of art. The art does not have to match the space. But thinking in terms of your color scheme, I pulled up a few posters, just for fun.

What are the dimensions of the couch? That is room is quite narrow. Is there no other way to place the couch so it doesn't face the kitchen?

Celery nailed it. was also going to suggest a rug and some type of bench or ottoman. 100%, get a rug the color is lovely. accent w/the lilacs/silvers/mauve/pinks/greens. the nightstand is nice. get another one. or something like tshown here this bed and side table is pretty. what about side tables like this w/similar lampls? white textured rug? similar headboards. look how they've done it: (not the colors, just the overall look) if you like the gray/white/pink, try copying the bed, rug and bench. you could do something like this with a natural jute or sisal rug