I think if it was something to deter raiders to avoid your settlement, you'd do something like:
Have a big sign saying "This will happen to any raiders we capture"
And next to this sign if a bunch of raiders who died horrifically by jamming them butt first on a long sharp pike that drives all the way up the bowels and exits out around the shoulder bone. If I was a raider and saw that, I'd turn around and run the other way. Or, say, Nuke the site from orbit.
Have a big sign saying "This will happen to any raiders we capture"
And next to this sign if a bunch of raiders who died horrifically by jamming them butt first on a long sharp pike that drives all the way up the bowels and exits out around the shoulder bone. If I was a raider and saw that, I'd turn around and run the other way. Or, say, Nuke the site from orbit.