First I would like to make a statement first: this build is just for entertainment.
If you take a look at the auction house, you would find that Diablo 3 Items with Attack Speed, Critical Hit Chance and Critical Hit Damage are all expensive. But this build would only require Critical Hit Damage.
Below is my Demon Hunter Pure Traps Build:
1. Marked for Death: rune Death Toll to get the Life Steal effect
2. Caltrops: Rune Jagged Spikes is the main attacking skill, giving 270% weapon damage over 6 seconds.
3. Shadow Power: Rune Blood Moon to increase life steal capacity by 25%
4. Sentry: Rune Spitfire Turret is really gorgeous with 170% weapon damage
5. Smoke Screen: Rune Choking Gas is used to run away
6. Preparation: Rune Battle Scars is used to regenerate Discipline
Custom Engineering: to increase the duration of Caltrops.
Perfectionist: reduce the Discipline cost and raise the defense.
Sharpshooter: make your critical hit chance up to 100%
It seems that there is nothing special for you to give damage. Actually, the damage output for this build would be surprisingly high. The main reason is that Caltrops and Sentry would not reset your Sharpshooter. You can remain 100% critical hit chance always. The only shortcoming of this build is damage reflect. So every rune is chosen for the purpose of Life steal. Another point you need to bear in mind is that you need items to support the discipline.
Now we come to calculate the damage. If your DPS is 100K, Caltrops damage is 45% and your critical hit chance is 500%, then ignore the monster physical resistance and damage speed elements, you will see that the monster damage taken can be around 200K. Of course, you could have higher damage.
The efficiency to slay the Champions is great as well. Three blow of Sentry are all with 170% weapon damage and all critical hit chance. You can understand the efficiency if you give it a try. Besides, Sentry would gain life while attacking.
It is still a little tricky when you encounter the damage reflect monsters. I am considering changing one skill and use Cluster Arrow. If you like this build, you can have a try yourself.