One thing that never seems to be mentioned with brighter screens is that they don't increase the amount of light at all. They are condenser lenses and focus the available light from the screen to a single spectator point. If your eye is at that critical point, the screen, and particularly the edges, do appear much brighter. Off-axis, the screen appears darker and on the most efficient screens can seem to switch off altogether. It can even be significantly dimmer for the other eye. With movements, this spectator point moves and can be difficult to locate, particularly with wide lenses. It becomes literally a pain in the neck.
Ideally, the focal length of the fresnel should be paired with the focal length of the lens. With long lenses a fresnel seems unnecessary. I switched to a less efficient screen because of all this.
This is not to deny that some screens, of any kind, are better-made than others.
There are other factors too. A coarser grind looks brighter but a finer grind is better for revealing detail. The actual surface shape of the grind may have an effect, too, but I don't really know. I seem to recall 35mm cameras claiming to have "laser-etched" screens. Laser-etching may offer delicate control of the micro-contours.
Other members of the forum may know more...