This is a great problem to have as the skies the limit. And you can easily change the look and almost do a complete redecorate just by changing the colors and styles of the pillows. You could go with a bunch of Crayola plain colors in clear brights, a modern look, or do tapestries in muted blues and greens with a few of the plain blues as backgrounds, a more traditional look. You have wisely chosen pieces that can go with anything and you can just give in to your conservative streak or your wild child nature. I probably would go with the round table though because the square uses up all the open space and is really too big, and the round one also softens the very boxy corners of the sofa.

Not a fan of the black? carpet. Something with color would look much better. Lots to choose from out there. See what speaks to you.

I prefer the round table, it's a better scale for the space. You need a pop of something bright, red or yellow would look nice with the blue accents, or perhaps a teal if you want to stay in the blues. A fun patterned ceramic lamp would be a nice accent as well. The current lamp disappears.

I don't mind the rug if you were to add pops elsewhere.

I would start by choosing a color from the artwork that I see I kind of like the black rug. I do not think the square coffee table looks like it allows anyone to actually move into the seating but I do like the looks better than the round one . IMO you need lighting so maybe an arc lamp from the corner of the sectional some tables and lamps at the ends , lighting works best when combined floor lamps, table lamps and pot lights.That seating looks large for the space so you might need to get a bit of lighting from the arc light if you choose one with more heads. Think about how people will put down a drink for sure.

Rug is actually navy blue with tan flecks. Photo makes it look darker than it actually is.

I love the pillows at Annie Selke - something with a bit more contrast could help connect the sectional with the navy rug

ETA - Arianna Belle makes custom pillows and will do a consult to help you put together pillows for a room. she also has a good guide on her website on pillow numbers/sizes depending on the sofa

So much potential, so before adding, consider a slightly different feel, moving closer to modern/coastal.

If you like this look, here are ideas. Also, take your time and look for sales and things you love. Suggest cushion covers, to save money and add a throw, large side table/lamp, adjust accessories on console and coffee table, highly suggest new sconses and instead of two matching art pieces on both sides, create more interest with different frames, sizes, mixing old and new for a more personal touch.