As you can see from the dramatic failures involved in the alternatives, they don't work very well.
Honestly, the only alternative I've seen to the killbox is the logic bomb defense, which works by confusing the enemy AI into going in circles until they all pass out or go insane. This is, obviously, not a stable method of defending the base as it relies on the AI not getting changed to not fall for this.
But honestly, I'm not seeing anything intrinsically wrong with killboxes. This is how defenses work in real life, too. Ever look at a medieval castle? If you're fighting guys who do not have siege equipment, this is exactly how defenses work in real life. Heck, my defense for my base is basically a piece of a star fort, a real life killbox.
Honestly, the only alternative I've seen to the killbox is the logic bomb defense, which works by confusing the enemy AI into going in circles until they all pass out or go insane. This is, obviously, not a stable method of defending the base as it relies on the AI not getting changed to not fall for this.
But honestly, I'm not seeing anything intrinsically wrong with killboxes. This is how defenses work in real life, too. Ever look at a medieval castle? If you're fighting guys who do not have siege equipment, this is exactly how defenses work in real life. Heck, my defense for my base is basically a piece of a star fort, a real life killbox.