I like it being priced high tbh. It just spreads out combat very quickly once both teams hit level 6 because the the shots are so fast and yet unlike the BR, the damage isn't spread out in a long burst. Some people are comparing the level 6 value to that of a sniper rifle but it's more than that. You can spawn with it for the rest of the game. 4 is definitely too soon, even for the basic variants. If you do that, the BR is going to get little time to shine in matches. It will be underutilized by players like the AR is, though for different reasons, obviously. I think the earliest they should be available is level 5 or 6.
And that's another thing, we have 9 req levels and Warzone is meant to take a while. If anything they should probably leave the DMR where it is, push the pistols back to level 2, and swap the BR and the SMG's availability so people are more encouraged to grind a bit with the automatics and play aggressively in the early stages. Right now it's just so biased towards precision weapons right from the the get go. Everyone switches to the pistol right away from my experience.