Ambulance called to property as the owner is having a heart attack, someone on either end of the phone gets the number wrong, they go down the street, to 28 instead of 82, are worried someone is unconcious and dying, they break in to try to help, you blow them away JUST because they are on your property.
Theres a reason why in the law property and location doesn't matter, danger to your own, or someone elses life allows reasonable force to be used and thats how it should be.
Said ambulance driver shouldn't be instantly shot upon walking into your house, you should realise he is no threat, explain its the wrong house and they find the right house and save a life.
In your world, you can kill them, and the guy down the road dies as a consequence on top of that.
INTENT, the same act can be commited for 50 different reasons, and intent is key in the way you handle situations.
Flat out being okay to kill anyone for entering your property in any circumstance ignoring intent would be ridiculous. Being able to kill someone in defending your life not proven but with a reasonable assumption someone is there to hurt you IS already fine.
Frankly if he'd shot them IN the house, he'd have no problem, but chasing guys outside, as they flee, he is no longer in danger. If they were running at him, the assumption they intended to hurt him is safe enough to make and blowing them away WITH A LEGAL WEAPON, he wouldn't have been in trouble.