Every class has to judge whether or not to pop a CD on CD or estimate whether they should hold off for a bit due to a proc while also knowing they won't lose a use of that CD on a fight.
The Energy regen issue and AoC are actually tied together, so to speak. Combat on Beta inexplicitly still feels like its being balanced around T16 Haste and CDR levels.
The scrapping of Readiness was an interesting situation. I feel like the stat worked fine for Combat Rogues, since we can actually reduce most of our CDs naturally by performing out rotation. However, for other classes, CDR as a stat would create extremely hard breakpoints on a fight to fight basis. The less uptime a powerful DPS CD has on a fight, the greater the benefit a class gains out of gaining an extra use.