Primaries actually need to kill about 25% faster....but only because that is what would be necessary to balance the game properly and end BOTH special weapon spam and grenade spam. The problem is that you've got a lot of Halo fans----both inside of Bungie and in the community----who simply won't accept this fact. But I played the Vanilla game. At a TTK of about 0.6 secs (compared to 0.85 currently) the game played in a much more balanced way, and the game had a VOLUNTARY primary meta, rather than the FORCED one we have now (such as there is, and what there is of it.) Primaries weren't well-balanced with respect to one another.....but primaries were well balanced with respect to special weapons and player abilities. But that balance was broken with the Great AR nerf of 2015 (patch 1.1.1) ....never to return. TLDR: This game was designed to play fast, and support fast play. Most of the Crucible's sandbox problems are the result of Bungie trying FORCE the game to play slower and to play like Halo. IN opposition with the game's design.