Your idea with these changes devolves down into "HURR DURR GUN TOO GUD" instead of WHY is it the optimal choice; and look into the variables that should be performing the role better and propose changes that make them a more compelling option against the Dog Ear; THEN adjust the gun accordingly against those to make sure it can still perfom without completely neutering it; for example the original Trouble Maker which took it from completely dominating almost everything barring extreme long range combat and vehicles to farting at people; and had been an entirely terrible choice for what, four years until the recent resurgence of it?
The other issue behind why the Dog Ear is apparently "too good" is that I rarely match against anyone who ever uses it. No one has any experience in fighting against it to counter it and underestimated it due the lack of adoption by people for a long time. It's a pressure weapon that requires aggressive gameplay and good positioning to do anything with; it's a 4 hit kill so you're hardly killing someone instantly.
Rhexx clearly has noticed that the DMR-AV has been lacking in it's actual role for a long time; as I have as well. I never used to use it as an AV gun and would consistently use it against players just because of my preference to it's handling compared to other snipers before using the Dog Ear almost full time.
Easy fix; buff the other weapons to actually perform their jobs and then adjust the offenders within reasonable limits of those so they remain practical and you're not limiting the scope of gameplay styles and preferences.
Crap like this is why I avoid the forums like the plague. It's a pissing match of people who are incompetent and cry about the smallest things without injecting any kind of critical thought and coming up with your own solution within the toolbox of the game; or they're just asking for motorbikes and the racing district.
But who am I; I'm just someone who's been invested in this game since RTW CBT; I it's not as if I know what I'm talking about or anything.