Asteroids can be a serious threat to the well-being of your ship. That is why I think we should have a dynamic in-game toggle key for "Asteroid Targeting" mode, on/off.
By default, this mode would be off. The current behavior of all weapon systems basically ignoring asteroids altogether would thus be preserved.
But if you toggle this mode on for the ship you're piloting, all asteroids are now treated as low-priority hostile targets. That means all point defense systems and other weapons will target asteroids (but only if there are no higher-priority hostile ships in range), and asteroids will be explicitly targetable like ships are. The readout for an asteroid should display something like "Asteroid, 575 tons" or something. The only reason for explicitly targeting asteroids like this would be to target them with missiles.
If you then toggle the mode off, and an asteroid is the current target, it will be un-targeted. Missiles that were previously launched at a targeted asteroid would not be affected, however (it isn't possible to re-direct missiles once fired).
And yes, Alex, this is really just so I can implement more SC2 ships
but I really think it's a legitimate feature for all of Starfarer