@Necromantion Little Birds in BF4 were one of the things that ruined the game for people for a long time (I was both on the giving and receiving end in my years of BF4). A good Little Bird crew was practically invulnerable and could literally cause the other team to quit in mass while they dominated the score board. Repair was eventually nerfed (after a long * time). OP helis are not fun unless you are the one piloting. You should not be able to stay alive indefinitely no matter how good of a pilot you are. Once the other team responds to you killing them and switches to AA/hacking, you should be dead if you keep attacking. Remember that forcing the other team to switch to AA means they can't take another gadget that might be more useful in actually winning a point/the game for their team.
