Awesome add-on, Topper! Absolutely excellent, just one nit-pick.
Firstly, do you think you will put in a option that turns off the deletion of the other craft? That way, people would be able to use it in movies and have dramatic "Mayday" scenes? You know the type. If not, think of the part of Pearl Harbour where the main guy crashes his Spitfire or whatever it is.
And a suggestion: Targeting your own craft. Yes, it does sound a bit stupid, but, again, it could be useful in movies. Especially you add an option so it only engages the guidance system 10 seconds or so after the launch as a sort of a "warning" time, giving the target a slight chance to escape... but it's your dream, do what you wish.
All the same, well done. Well done indeed.