It's hard to make suggestions without seeing the room and/or knowing your style. Here are about 2000 ideas to get you started:

https://www.houzz.com/photos/dining-room-with-red-walls-ideas-phbr1-bp~t_722~a_46-341

Frankly, I would consider repainting the walls. The red color makes this space look very closed in. If the wall with the opening in it isn't weight-bearing I would remove it.

I agree with Elle's suggestion above. On a side note, I love your Christmas table settings; the santa hats are cute :)

Do you love the red? The wall color is so strong that just changing curtains and table decor is not gong to be much of a change. If you are tired of the room, paint is going to be the easiest and most dramatic change.

If you like red, there are gentler, browner reds / rusts/ spice colors that would blend better with the wood and floor. Another red over red wouldnt be that hard to do. As far as window goes (is there just the one?) a woven woodsy type of shade to relate to the wood elements or curtains with simple pat]tern incorporating reds/browns/whites.

I went with silvers, black and a little white in my red dining room with dark wood furniture. I have been trying to decide how to change this room for years but can not pull the trigger on choosing a new scheme.

i love your cherry art work and would incorporate the white with red into the room more.