You shouldn't need any type of informational feedback. If you need any type of meters in order to succeed, especially in a raiding environment, you are just a poor player. Honestly, I feel the inclusion of health and energy bars also makes the game too easy. A good player instinctively knows when a party member has low health or when the healer is out of force, and especially when hes about to pull aggro and wipe everyone.
Also no meters makes the game more friendly. Without them no one yells at me because I only use my basic auto attack during flashpoints while I watch TV or play with my cat.