Any reason why we should have a missile early warning system other than "it would be a good idea"?
Your proposition will cause an end to Stealth and Ambush Combat, you would seek to completely nerf the ability to conduct any form of hit and run sneak attacks, Missiles are the best alpha damage and the longest range, so they are frequently used for alpha strike hit and attacks, giving people a warning that they are being locked onto with a missile completely kills the point of even using stealth to get into an optimal position for taking out a vessel with missiles. Cannons, beams and damage pulse cannot preform this role.
Missiles to not need to be nerfed, they already have considerable drawbacks that steers lots of players away from using them
They take extreme amounts of power and power capacity, a small ship can use cannons without the need to place any power capacitors, and yet any small ship in order for a missile to be effective would REQUIRE a large amount of capacitors, removing space for other system components.
They have TERRIBLE sustained DPS, they have good alpha damage but they cannot sustain a constant damage stream unlike other weapons.
The missile projectiles are extremely slow, the amount of time from when you fire a missile to when it actually takes down a target at typical engagement ranges is about 15 seconds, assuming that said missile is not shot down by point defense systems.
Overall, a lock on warning has very little benefits and kills 2 forms of combat in StarMade, the only other form on combat in StarMade is big ship vs big ship slugfest, and we all know the problems with that.