Ok, It's late in the UK. 20 to 1 in the morning. I'm freakin' tired. This is more than likely a non-sensical brain fart. Just roll with me though.
What if there was a healing class which used energy as a resource, much like a rogue. Let's say they start with 100 energy, just like a rogue, and regen an unchangable amount of 5 energy per second (I'm assuming this class would have an inherant 1sec GCD as opposed to the conventional 1.5sec GCD). They would need to have 3 heals, as well as some CDs to be similar to normal healing classes. These would be;
[Slow, Efficient Heal - Costs 8 energy, 2 second cast time. ] The idea behind this is that this spell is similar to a paladin's holy light spell. It doesn't heal for much at all, but it can be spammed forever at pretty much negligible cost and allows a small amount of regen to occur while being cast.
[ Slow, Powerful Heal - Costs 25 energy, 2.5 second cast time ] This spell would be equivalent to a paladin's Divine Light spell. Spamming of this spell would result in a net loss of energy, but not as fast as the next heal.
[ Fast, Powerful-ish Heal - Costs 25 energy, 1 second cast time ] This spell, like a paladin's Flash of Light spell, totally 'rapes' your resource, but provides quick, fast emergency heals.
[ Instant, Low Heal - Costs 10 energy, Instant ] - Heals for the same amount as the first heal, but for slightly more resource and has no cast time. This spell would also most likely be spammable and have no CD.
Now, CDs.
[ 20% haste increase - 20 second duration - 2.5 minute CD ] A CD for when damage is occuring fast. When activated, puts all other CDs on a 30 sec CD to stop all CDs stacking and allowing for imba healing.
[ Instantly restores 30? energy - 3 minute CD ] - CD to save someone with a large heal when you're low on resources. Would initiate a 30sec CD to stop CDs being stacked.
[ Increases Energy regeneration rate by 100% and healing continues at 75% efficiency - 10 second duration - 2 minute CD ] Allows you to spam more heals, but they heal for less. Initiates a 30sec CD to stop CDs being stacked.
So yeah, as you can see I have some rough outline of a design of a new healing class. I will probably add to this IF i get bored enough and I get positive feedback! So yeah, let me know what you think, and as you can tell, it's all very rough atm :P
EDIT: To stop Spirit and Intellect being null stats, I have one idea. Spirit would instead convert itself into Spell Power at the rate Intellect currently does for other classes. Intellect for this class would however lower the overall energy costs of spells as well as providing spell power at the rate it does to other classes. This would be inherant of playing the class and would not be talented.