+1 GG
We can compare Arma and DCS simply
Arma have great details of littles objects, like in a classic fps, but take a plane in arma, and you see you have a circle of view around you, you have not a great visibility like in DCS.
DCS have clickable cockpit and realistic physics rules, for Arma3 i think this is the same as the 2, two click for start up, one click for lock, one click for shoot :D
In Arma you have not an accurate damage model, let see for the 3 but...
Arma as not the focus to be a flight simmulator, an infantry one, maybe yes, but with simple system for vehicles, for everybody can use it!