Well, I can give you my thoughts, but I suspect there are many more qualified on this board who can offer real-world, self-defense, household security advice that I am not really best suited to offer up. (Preparedness is my gig.)
First question that I have is, how old is your daughter? That could have some bearing on how much responsibility you can put on her to react in certain, preordained ways given various threats.
I also wonder about your neighborhood and the threats you feel are commonplace around your home. Perhaps not only crime, but potential threats from fire, storms, earthquakes, etc. could play a part in your planning.
In general, if there is real danger for your daughter--I would probably look for a way to harden her bedroom--door, windows, maybe install an intercom. A well-designed, monitored home security system may also deliver some peace of mind.
I don't have an opinion on the lighted key out the window thing. Not sure if that is of value or not--perhaps an LEO can respond to that.
Lastly, I think we are at the point in this society where you usually want to be very careful about any possibility of self-incrimination. An attorney would be well-advised in any self-defense investigation by police.