Very nice article...
I want to focus on the three explicit definitions of Cleric (of course the religious aspect is also a major definition, but not so directly into the mechanics):
1. The Cleric Is a Healer
2. The Cleric Is a Divine Spellcaster
3. The Cleric Is an Armored Warrior
I think what has actually caused some problem and controversy is point 3. Personally I used to think that the Cleric was originally given armor more as a compensation for the fact that he lent the healing services, often to be done performed in the middle of a battle (hence the extra defenses, so that he doesn't need to risk too much), rather than really making him a good fighter. I strongly believe that as soon as you have enough spells per day, you can play a totally powerful Cleric without fighting in melee, just casting your spells.
But given the armored warrior concept, I think too many people focus on this aspect of the Cleric as if it was the most important, and then of course they complain that "healing wastes my time, I should be rather fighting", and also choose too many combat/buffing spells to become even better at that. What is even worse, they use all their buffing on themselves, instead of supporting others, and then the others complain about the CoDzilla problem.
All this in light of the fact that at the same time many other gamers are unsatisfied by the lack of a Cleric more similar to RL priests, hence less battle-oriented.
I'm going to stretch my opinion here, and say that perhaps it would be for the best of all that the Cleric would be given very good
defensive melee abilities, but very poor
offensive melee abilities, so that even when self-buffed it could not outshine the fighter-types, and that in general fighting (i.e. attacking) would not be normally more convenient than spellcasting, unless of course you're out of (useful) spells.
See also my next point...
I think the goal for designing a good cleric class should be making the Healer as attractive as possible.
Few players want to heal the party, but they all want someone to heal them. Reward the person who is willing to be a team player and heal the party. (I do in fact take one for the team often and heal the party.)
I think this is an important remark!
What bothers me, is that not only few players want to heal the party... but also not so many players want to buff the others, or directly shield the others, or aid/support the others...
Personally I think it's about time that D&D would promote more
teamplay, but it has to be proactive not "automatic-in-the-background", which is quite the opposite in fact... having a PC with an ability that all the time grants +X to all comrades or that automatically heals a wounded friend is not what I like, because
if you're not paying a price for using it (e.g. give up your action) then it's not really teamplay, it's the opposite, it's "I don't need to bother because the game does it for me, so I can focus on me, myself and I".
I understand that this idea is controversial, and most gamers would very much prefer to go the other way. In my case, I think it comes from having in the past years promoted RPG even at work, as an exercise to develop cooperation and teamwork, and "unfortunately" these are things that require care and effort... although I probably would like if in my profession I could have some "automatic-in-the-background" abilities that take care of my workmates requests for help and answer their questions while I can keep posting undisturbed on ENWorld... I mean while I can keep working.