I would like to start by saying that I absolutely love this game, even in its current state.
However, there is one massive issue I see with this game, and that is Team Killing.
In my opinion, the ability to damage teammates should just be removed from the game. There is no upside to being able to damage your teammates. I have played games where a moron will just sit in our spawn, shooting allied vehicles with the TOR, or following friendly tanks around shooting them in the ass with AP rounds.
Even if it doesn't get removed, I suggest that the current system should get a massive revamp. In the situation I mentioned above, where morons and trolls will spend all game shooting friendly vehicles; if the person in the vehicle shoots back and kills the troll, the troll gets the option to remotely kill the guy in the tank. That's right, you can spend the whole match shooting friendly tanks, and doing damage, but if they dare fire back, you can just kill them with no repercussions.
At the very least, the revenge kill feature should be removed as it is far too easily abused. I've accidentally ran over teammates only to suddenly die, and have my tank destroyed because someone couldn't tell the difference between an accident and a malicious act. Instead of the revenge kill, perhaps add a vote kick feature, or an auto kick if a player deals enough damage (specifically damage, not kills because you can just walk around shooting tanks or infantry without it killing them) to friendly players.
Thank you Farm 51 for making this amazing game, there are just a few things I think should change, and this is one of them.