Did Bungie ever say why they got rid of the covie sniper? I liked that sniper more than the human one.
Goal for Reach was to remove as many redundant weapons as they could. Beam Rifle was probably a relatively easy cut. You weren't even able to start with it in 3.
So instead of the sniper, they took the Beam Rifle's silhouette and then kinda melded it together with the Sentinel Beam to make the Focus Rifle.
After seeing Heretics in Firefight with Sniper Rifles, I think I'm glad they don't have a Beam rifle in Reach. Because then there would have been a spot with Beam Rifle Jackals and I would have just bought a plane ticket and drop the disc from the sky to watch it shatter into millions of pieces.