I usually like to blend in with the wall, especially when you have several small windows.

My suggestion is to do a neutral color, but pick a fabric with texture or a subtle tone on tone pattern.

Obviously you like color and texture. A beautiful space. I think it would work to install a very neutral roman shade on the windows on the fireplace wall and a bold print upholstered valance or roman shade on windows each side of couch.

It depends on the look you want. If you want the shades to stand out and be a focal point, then go darker than the walls and trim. Keep in mind though that dark window treatments block light and can make your whole room seem darker. Light shades will blend in with the walls but will allow light to filter in. You could also select a patterned fabric for the shades which will add interest to the room.

You can absolutely go either way - contrast will add some interest to your spaces - where blending will keep your space more neutral. If you love your red, and can see accenting with it for a long time (5 years, plus) then go for something fun and colorful. If you like to change your accents with the seasons - then if you go neutral, it will be easier to switch things up.