Looking a lot better now. You need a lots more particles. Don't make a giant particle cloud over the entire scene. Just set up multiple smaller particle clouds set up directly in front of the camera. I wouldn't use spheres I would use facing particles with an opacity map like this.
that can be done in the materials window and then just assign the material to the particles like you do to any other object. Your particles are also moving way to fast. I would also set up a wind force with the strength set to 0 but the turbulence set to 3 or 4. then space warp bind the particle clouds to the wind. that will make the particles slowly move.