looks really the good, really like the images you have used. But as Golem said the "of RWANDA" part needs to stand out a more. The cut off on the "GHOSTS" is okay, but not on the rwanda when it's that small. I would make the Rwanda bigger, close to the ghosts size, maybe make the ghosts smaller so it doesn't get too dominating.
My covers may only be viewed on well calibrated screens and printed on well calibrated printers.