Help Me Decide, Pleeze

You dudes may remember the bedroom makeover I started a hundred million years several months ago.  Well, we were moving right along, then I got busy with work so the project got put to the side for a bit.  I'm ready to wrap it up now but I am at a MAJOR impasse:  I can not decide what to do with the walls.  I have one black wall, which I love, and the rest are white, also great.  So, what's the problem?  I want to do something to the white walls to make them a bit more interesting and to make my headboard stand out.  Let's start with a pic of the room now:

Sorry, I'm no Erin so the picture isn't so great.  The curtains are going to be rehung a few inches higher, art and lighting are still being picked out, and I'm thinking of getting this rug for under the bed:

Yes, we have all seen this Ikea rug before.

I thought doing something simple like this on the walls would be good, but I'm not sure the headboard will stand out enough:

I don't have to do a laser light show, I could vary the shape:

Or should I do something with subtle black lines to tie in the black wall?

I'm really open to any and all suggestions, even if you want to tell me to paint the whole thing kelly green (which I probably won't do, but girl, I will listen!)