You can prevent raids (except for 2 I believe, those are 'You are being Hunted" and one other) by not having any craft stations or camp fires in the area. My lesser defended outposts, I remove the workbench after I am done building and remove campfire also.

I have had raids where there was only a bridge because I had multiple workbenches there. So I remove workbenches after I finish a bridge as well.

You can't have the best of both worlds. What I mean is that workbenches have a radious that prevent normal spawns. So you could carpet an area with them to prevent regular spawns, but then you get raids nearby instead.