I really like what Pathfinder did with the channel energy ability (replacing turn undead). However, I don't think they went far ENOUGH. Here are some of my suggestions for updating the channel energy ability of clerics and paladins:
* Make channel energy a range of touch. This would would replace the paladin lay on hands ability entirely.
* Add feats that would alter how channel energy works. Channel Energy Ray would focus the ability into a ray of some range. Channel Energy Burst would create a burst of energy with a range of personal. Channel Energy Cone would affect everyone in a 60 foot cone. Etc., etc. Create another feat that would allow a user to use positive or negative energy (at will? take up an extra slot?).
I like the progression and the steady supply of healing. I like the fact that it harms undead, which makes the ability useful against undead but not useless against non-undead. It becomes a very usable ability of the cleric or paladin in most scenarios.
Discussions welcome.