I also really wanted to see soul harvest changed to reflect the strength of the soul harvested. For example, white enemies give 1 stack (as it functions now), 1 minion harvested gives two, elites give 3, and bosses give a full 5 stacks. The mana return and life return should scale with the strength of the soul harvested as well.
I really wanted to see grave injustice changed a little as well. I was hoping to see a cool down affix added for health globes as well, e.g. globes dropped by white enemies reduce CDs by 2 seconds, globes from minions reduce CDs by 4 seconds, globes from elites by 7 seconds, and globes from bosses by 10 seconds. This would make the skill somewhat useful in all encounters.