With this layout, painting the walls just within that space is going to be a little tricky. I like the idea of painting the front door though. If you want to do an orange maybe go for a yellow-orange like an amber that will tie in with the yellow accents in the living room. As for the pillar, just ignore it. Anything you add to it will just highlight it and make it stick out more.

I think it would be fun to paint the walls on either side of the stairs up to the main level orange. Only paint the flat surface, not any returns.