That iron headboard will look terrific against that shiplap wall - much better that the upholstered headboard in the pic.

Should I stick with white..what do ya think

You can do as you prefer - it's your house. But you do realize that it's a bit of a cliche these days.

I think I would stick with a pure horizontal shiplap on the three angled walls. I would not do the design of the shiplap in the last picture because your wall wouldn't look like that picture.