I like David's comments above and think that you should select a simple large (12x24") tile for your fireplace, light or dark.

What about mosaic tile? Lots of colors, styles, sizes, and finishes to choose from. You can also mix tiles or keep it simple and uniform - whatever you prefer! This fireplace was done in a single color of iridescent tiles, very sleek and modern! (other colors available!)

Is that a window in center above the hearth? Is rock just a facade? Looks like you have a mixture of furniture styles. Windows look more of the modern style while drapes are traditional. I would say pick one style and go with that. From the windows I'd be leaning modern/ contemporary. If the rock is just stuck on wall take it off. Replace with horizontal wood planks stained same as your door casings. No mantle. If that is a window I would either have a stained glass insert made (again using modern lines) or do a faux stain glass painting treatment to add some visual interest.

Buy the bedding you love and then go from there to doing the rest of the space, paint is cheap so leave it till the end of the process and match to something in the bedding would be my suggestion.