Personally I don't think Bogeymen exist, I think they represent the natural drive of insanity when all alone.
I've heard this theory before, but it doesn't hold up to when they start attacking wildlife or when nearby villagers and soldiers come to your aid.
This is the way it should be imo. Don't get me wrong, it's cool to have murderous shadow creatures attack you every night as the game's in development, but the certainty of it forces you to plan around it. If they've got to be indiscriminately murderous and unarguably existent, I'd rather they be linked to regions in worldgen - not necessarily evil/terrifying/haunted regions, either.
So then I claw my own eyes out at night from loneliness?
Maybe if they were more mischievous, like stealing your things and pushing you into pools, tripping you, climbing on your head, dragging you up on top of a tree or something, than purely aggressive then they'd be more of an entertaining nuisance than the absolute terror they are now. They do drive me insane whenever they end up making all the lucky shots and tearing off a limb or punching me in the face the first round.
I'd love to see variations like this.
I remember there was a bug where bogeyman kills turned into wildlife kills. That could be reintroduced as a feature; some "bogeymen" would just be your eyes playing tricks on you.
edit: Oh, oh! But something I really wanted to say: you can sneak when you first hear the cackling, at least if your speed is high enough. Then just make small movements to keep bogeymen out of your visual range without going far enough for them to teleport to you. Wait in place until morning, and the bogeys shouldn't ever see you even if you have no ambusher skill.