I doubt DH-Havoc's dmg will be nerfed by a big margin, maybe a bit toned down but nothing big, i mean DH does not have anything else but High dmg, its their lore, DH's do not off heal, do not have insane spammable CC, and its a new Cash-Cow Class for Blizzard, they will keep it strong, not stupid OP but definitely very very strong, so i think the most you can expect are minor adjustments and tuning