If you are keeping the current window treatment and staying neutral with the walls I would go with a tufted upholstered headboard, like the one below. I think the tufting of the headboard kind of plays off of the pattern you have going on the current window treatment. I suggest a neutral colored headboard because it is typically more affordable to swap out the bedding rather then the headboard every time you want to change the color scheme. Now as far as the bedding color scheme goes.. I say go with a big pop of color! You are really able to have fun with this because you have stayed neutral in every other category. I suggest this Aurora collection from Pottery Barn-

Did you mean to paint the headboard you have? Have you browsed at bedding?

No, I will change it totally. And also I am browsing for bedding.

What colors do you like? Do you want a fabric headboard? I bought this headboard from Amazon for $150.00 it looks like linen.

Here are a few ideas:

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