Covenant Sniper and Sentinels

Yeah its me with a New Pointless Topic. Anyway, we have seen some Kind of Prometean Sniper (im not talking about the Light Rifle, i said Sniper, not Rifle) on the Spartan Ops footage from the E3, but not Gameplay yet. I would like that sniper to be a One Shot sniper (like the Longshot from Gears of War), but thats not the Point.

We have seen two Covenant snipers on the Previous Game; The Focus Rifle, and the Beam Rifle. It would be cool if the Beam Rifle returns and the Focus Rifle disappears, because, if the Prometeans were Created to destroy Flood, there have to be Sentienls also, and their Sentinel Beam works a lot like the Covenant Focus Rifle, but in Short Ranges.

Thats why I think that the Focus Rifle had to be changed to the Beam Rifle, because a Focus Rifle is Annoying (Both using and Taking Fire), and if there Sentinels, wich arent Confirmed yet, we are Going the have the Same Weapon basically, but long and short Range.

PS: http://www.youtube.com/watch?v=vAKmu2yn3Fk You can see there a Sentinel on the Minute 0:40, so is very Possible that they are Back, and their Weapon as well. I Think.

Discuss… and sorry for my very Bad English…