I just had some time to waste, and thought why not drop here some important development concept (in my thought it's important). I'm 95% sure that this will also end in the infinite void of the forum, but let's try.
After years for trying to have fun playing the Arma series, and after slowly lots of improvements were made in the "game-breaking" areas, like the netcode etc., I feel that the (joyful) playability of the game as a military simulator is still limited. I have lots of issues with small technical aspects of the sim, but let's drop those now, because the forum is already filled with that.
I finally realized, especially after seeing the success of DayZ, that Arma as a product was never good as a game, but only as an engine and a framework. For a game to work, you need a worked-out entertaining game concept that has a flow and stimulates the players. Even thought thousands of peoples in the community were tinkering and building thousands of missions and hundreds of mods and addons, the military sim part never really worked for me, never felt that this had a working game-flow concept. With the exception of the few thousand people who grouped in organized game communities, the multiplayer part of the game didn't work as an ad-hoc join up thing like with other games. And this is not because it tries to be realistic, or being "hard-core", just because it's not fun, it has no flow.
DayZ proved that you achieve the flow with some good concept, and you can build upon the engine to make a good game. But I don't really like zombies, I would like to get back to the military simulator concept, and the question of why did it not work (for me).
The best attempt was with project reality, which is a very well made game concept, but after some attempts I still felt that this is far from a war simulator. I waited for more people to join up the server until I played with 100 players but still then it didn't seem like a war simulation because of the lack of a real frontline. I always tried to relive the moment I had with Planetside which even though had an arcade like shooter mechanic, always felt like a real war simulator with frontlines and organized troop movements. I never had this kind of experience with Arma (or any other game), and finally I realized that it's just because you can't simulate a war or a battle with 50 or 100 or even 200 peoples in a vast areas like in Arma. It needs thousands of players at least to ignite the reaction of a war simulation.
So I would say that maybe it would be a good idea to consider the direction of going into a massive simulator area, and making the game engine capable of cluster based server systems. I'm not saying that Arma 3 should be an MMO or so, but at least the engine and the server side system should be capable of doing that. Maybe some other company will produce an MMO product with the engine, or the community will do something like that, like with DayZ (even a mod like DayZ could really evolve if such an architecture set up would be possible). My great dream is to play with a massive war simulator, which has the graphical aspects of Arma but the massiveness of Planetside or even exceed that. The only other game concept like that is WW Online, which has a base engine from the previous century. I'm sure the company who will manage to produce such a game, will win over the industry. And also don't forget that maybe the VBS division could benefit from such an architecture too.