I think a useful feature would be to create the ability to draw and place markers on the map. The way I see it there are a couple different ways you could do it, all of which have potential to be very helpful. Arma 3 uses a map where you can choose who can see your marks, only you, only your squad, only your team or the global option. As someone who enjoys long range bombing it'd be nice to draw myself a route or make notes on the map that I can use for future reference, so even if it's something that's only used on a personal level, it still has potential to be very useful. It would also create a way for teams/squads to communicate information, faster, easier, and more accurately. All map markers created to be seen by your team/squad should be able to be deleted by anyone on your team/squad to prevent someone from cluttering the map, and we should leave the option to hide any markers for people who don't care to see them.
Maybe this is an idea that has been presented in the past, but it wouldn't be that hard to implement and has potential to be super useful. What do you guys think?