The critical multiplier is the point. That is why players chase crit X in trees, feats, or weapons. Crit X is exponentially greater DPS than Damage %. What is the purpose of Sniper Shot? It is to take out a single target with one huge alpha strike. This functions in heroics as designed. Sniper Shot on its own no longer does that in Epics because your standard trash mob in end-game play has 8K-16K HPs. Hunt's End functions as a force multiplier to Sniper Shot allowing it to perform as designed on Epic mobs. Removing this effectively destroys the ability in Epic play. The entire purpose of a sniping archer - remove that Epic Demon Soul Champion is now gone, replaced by hey let's hit those two mobs next to each other, if they don't move, (remember in new quest design mobs don't trigger and can't be targeted until you're virtually on top of them) for 10% extra damage. Congrats, we just hit two mobs for 3500 damage who are now agro'd on us instead of deleting one mob as a hunter sniper is supposed to do.
The deflect carryover is another massive change. Primarily because game design tends to revolve around mobs that have a ton of deflect or none. So let's take Skeletons in the Closet. Already an annoying raid to deal with trash on ranged it is not uncommon to have four deflects in a row if melee hasn't prepped a skeleton. But at least on your 5th shot, you'd trigger your Hunt's End. Now you might never effectively land Hunt's End in a raid like Skeleton's in the Closet. The strike rate would probably be 20-30% depending on your luck. And if you just have to sit around waiting for a mob to be prepped by ranged with an ability that causes drastically less damage without Sniper Shot, what's the point of even having a ranged build in the raid?