I like that, but I'm concerned that if that's actually the size, it would look too big between those windows. I think you're better off with a grid of 4 of those in that space, just smaller. It will seem less cluttered. Definitely find some additional accessories in those colors though. I think that would look really good in that space.

What color is your couch? Is that dark gray?

Love 1 and 6!

I like the art -- might try to get a narrow dark frame, though, just to ground it with the dark furniture et al. and help it stand out more.

Yes the art work works. You just need to hang it exactly in the center of the wall and straighten it. I agree with the comment above to do a narrow frame I will do it in black it will bring out the colors from the paint and from the grey wall. I will pick up the colors from the paint for the pillows but I will do it in a solid color fabric like silk so it brings shine to the space. The paint has to much movement and you don't want to make it too busy with the pillow fabrics, maybe just one with design and that one do it in grey.

I would get the 24"x24" to leave some breathing room between it and the window molding.

I really like the 36" x 36"- colour and size are great.

Have you considered making your own using those same colors? You could buy some acrylic paints and a blank canvas, size of your choosing, and trying to replicate different parts of the art. That would likely be cheaper and custom, which it seems you really want.

If you decide to put a painting there, I suggest you hang Roman Shades on the windows. Posting this photo not for the art or fabric but to show you that you need more up on that wall to balance out that art work. Your sectional is very big and it doesn’t look like it can be pulled away from the wall, so panels of fabric won’t work for you.

Once painting is chosen, choose your fabrics.

Enviable Designs Inc. · More Info

Also, I am having trouble with the turquoise as accent in your scheme. Leaning more towards red and layers of gray.

'Romantic Sea' by Preethi 24"x 18" Original Modern Painting · More Info

For what I can see in the picture you can go with the 36" X 36", it looks like you have 3" on each side from the window frame so it should be OK. If you decide for the 25" X 24", I would do a thicker black frame so it stands out, that painting will be the focal point of your space.