Instead of impact style weapons (mic, laser, rail gun, rpg) just having a hit-miss system where if they fire they would either do a specific or randomly calculated range of damage, or not hit at all, I propose that damage be directly related to the angle of impact.
A hit perpendicular to the hull of the vec would do the most damage, but a glancing blow would do significantly less, and all angles in between.
Because Op3 is 3d that may be enhanced even more with angled hulls to lesson and deflect the impact (just like in real tanks)