Seriously it's the equivalent of removing sinister strike from outlaw rogue and linking all their combo building to passive auto-attack. When switching from demon blades to immolation aura spec we go from zero to three builders (demon bite, immolation aura, eye beam). It requires way more paying attention to resources and cooldowns to pull it off.
If anyone feels like DH are too simple then blame Blizzard for making passive talents superior to actives. Same goes for them nerfing momentum build, the most skill-based DH spec of all.