I have all the settlements in game plus few more that I made using a mod - they are all very well defended and have 24 settlers with the best armour and weapons. The chances of being attacked at any of them is 2%, so I go days if not a whole week or more without anything happening, and if anything does an attack, I don't even bother going because I know it will be defended.. I use mortal settlers, and I get the odd casualty, but that's life I think the last time it said I failed to defend was when I was around level 50 (I'm 150 now)...Everyone of my settlers were killed, the power and water needed repairs, but the whole thing was back up and running and new settlers filled it back up within a few days Besides all this, If someone does make this mod, I think It would be fun.. Just because you cant handle it, doesn't means no-one else can