Isn't the biggest reason why we can hit things from 800 out is because of the icon??? fly icons of and you'd be surprised how close you actually get without the range computing.
As has been said elsewhere, removing icons will actually make things LESS realistic. It's not the icons that make gunnery too easy at long ranges, unless it's a matter of the range indicator being too precise (thoughts: what would you all think about showing the aircraft ID and, if the rate of closure or opening is sufficiently high, giving a + or - to indicate this, but NOT showing the actual range?).
The real problem I think is the environment. There's not really any air out there; it's a vacuum. There's no turbulence, prop wash, slip streams, thermals, high and low-pressure areas, none of the myriad little factors that would impact flight and gunnery. I think it's been confirmed that ground effect does exist, and the last time I flew I think I saw wind layers being used in the Mains, but the wind is at a consistent airspeed and direction in each altitude band, with no gusting or direction changes, but otherwise the game is a static environment.