I originally went looking for cheats that boost the dismemberment after being unsuccessful I took a look through the game files. I was able to make several changes that made the game a bit funnier. This mod makes the game more gruesome and a bit difficult more.
Follow the follow path then unzip to replace the original files:
-After fighting 30 guys in a corridor you expect to see bodies piled up to the roof. Now you do.
Max dead body count raised to 60
-Gun bullets can destroy and rip off limbs
-Gun blast can rip off limbs
-Slightly reduced the chance of guns destroying limbs
-Crossbows rip off arms and legs (Sometimes pins them to a wall as well)
-Explosives blast enemys apart
-Your sword fast swing is far more likely to sever limbs
-Windblast can tear off limbs
-Guards glance longer
-You can't lean quiet as far. (Corvo used to lean 60 degrees around corners without being seen)