So it sounds incredibly specific, but if most people's theories that we'll end Normal/begin Nightmare around level 30, I started thinking of a build that would work then (and I have too much going on with classes/work to marathon like I want to, so I might spend more "time" [irl] at these levels than a lot of you--who I am in fact jealous of).
1. PD could easily be changed for Jar of Spiders--Widowmakers. I just figured I like having the specific target ability.
2. I love Resentful Spirit. This is obviously my focus attack for champions/bosses, I thought about Locust Swarm for the sake of synergy with Bad Medicine, but the range doesn't seem nearly as good.
3. Acid Cloud gives AoE damage/poison to keep the enemies damage down (thank you Bad Medicine).
4. Soul Harvest. Even with theories on diminishing returns, at this level I doubt that will be a problem. I have it on life at the moment, if I find Mana a problem (I don't think I would with this setup, but if so I can swap out Siphon for Swallow Your Soul).
5. Dogs. I want everything to be poisoned at all times.
6. Restless Giant is pretty solid. Big Stinker fits more with theme and synergizes with BM better, but that isn't unlocked until Level 48. So yeah.
ZH is obvious, extra dog and more health for them and Garg. Jungle Fortitude makes us all more fearsome. And Bad Medicine, because I want everything I come across to be green.