it looks to me like you have really maximized your space in this bonus room. i'm afraid anything you did on the wall/ceiling above the fireplace would just accentuate the slope. you may want to try a deeper mantel though, so that you could place taller items on it.

Yes. Great idea. I would love to do a nice big, more substantial mantle. I wonder if its possible to notch out the drywall somewhat. Any builder/decorators out there?

I saw a room like this that had done a strong colored terra cotta or light gold finish (like plaster) on all the walls and ceilings. It really brought the entire room together and made it cozy. The slopes are there, but blend them into the walls and it will make them feel more like walls than ceiling. I would definitely remove the bricks above the mantle and sheath the stone in a slabs of limestone or something neutral. I would also suggest a larger, more colorful rug to liven up all the leather. Colorful pillows and accessories and the room will be much more inviting. I would say it is time to swear off brown leathers for a while, too. :).

Walls and ceilings are same colour. I have bright carpet for fall/ winter. Oranges and reds. Like to lighten up for summer. Have pillows too. Thx tho

Oh there are no bricks. This is big slabs of natural stone. I forget what it's called. :)