If I had a stick frame house, I'd put concrete planters around it where I needed
ballistic protection. They look normal, so they don't attract attention, plus you
get 2 layers of concrete with soil in between.
If your floor can take the weight, sand bags against exterior walls is a good idea.
You might not put them everywhere but at least where you expect to have a
firing position.
Our house is a bit odd -- it's a berm-wall construction, earth sheltered home,
which has it's own issues. If I were getting skittish about security, I'd buy a
bunch of security cameras with wireless connections to cover my blind spots,
and one or two looking back at my place to look "over the shoulder" of anyone
trying to sneak up on us.
Bear