there's room for paladins, melee clerics, and spellsy clerics
I'm going to veer off into Paladin territory for a bit before coming back to clerics.
I think it would be unfortunate for D&D players to conflate the Paladin with a Cleric by classifying each as a “holy warrior” or "warriors of faith." If we look at all the iterations of the paladin from 1st edition to 4th, we can see that paladins, while good were never “holy” and not necessarily "faithful." Dedicated or committed, yes - but not necessarily demonstrating faith in the belief of a god or entity that would grant them divine power. They used holy weapons and such, and even had access to spells at one point, but that doesn’t necessarily make the paladin equivalent to a cleric.
On p.18 of the original 1st edition PHB, it says, “paladins are fighters who are lawful good… “ and the beginning of the class description for paladins reads like this:
A paladin character is a fighter sub-class, but unlike normal fighters, all paladins must begin as lawful good in alignment (q.v.) …
In 2nd edition, the description of the paladin changed slightly, but it still emphasized the fact that a paladin isn’t necessarily “holy” or that he is part of the clergy. On page 57 a paladin is simply a heroic and noble warrior:
The paladin is a noble and heroic warrior, the symbol of all that is right and true in the world. As such, he has high ideals that he must maintain at all times.
On page 51, the 2nd edition PHB continues to emphasize the martial aspect of the paladin, but it doesn’t confuse piety with holiness or conflate a virtuous dedication to an ideal with serving in a priesthood or exercising divine power due to one’s affiliation with a church, universal concept, or deity (i.e. as does a cleric). However, it does start to broaden the concept of the paladin by incorporating the concept of the paladin being an exemplar:
The paladin is a warrior bold and pure, the exemplar of everything good and true. Like the fighter, the paladin is a man of combat. … He strives to be a living example of these virtues so that others might learn from him as well as gain by his actions.
In 3.5, the description changed again, allowing a broader interpretation of what it meant to be a paladin. The focus on the paladin being a fighter was lost and a greater emphasis was placed on the paladin’s personal virtues. This is where 3rd edition took a cue from 2nd edition and enlarged that language to a state where I felt that shifted the concept of a paladin from a simply lawful good fighter concept to something that drew closer to a cleric.
The compassion to pursue good, the will to uphold law, and the power to defeat evil—these are the three weapons of the paladin. Few have the purity and devotion that it takes to walk the paladin’s path…
4e painted the paladin with even broader strokes, even though it did emphasize the distinction of the paladin as a warrior. the PHB describes changes in the paladin allowing variations in alignment and the ability to be dedicated to a cause or concept rather than simply to a deity. However, on p.89, the PHB continues to emphasize the core of the paladin class:
Paladins are indomitable warriors who’ve pledged their prowess to something greater than themselves.
My personal preference is for the 1st edition definition simply because of its simplicity. A paladin is a lawful good fighter who is nobly dedicated to a particular cause. I don’t really have a problem with a paladin not being restricted by alignment, although it makes sense to me that a character that is driven by a particular ideal might be disposed to a lawful alignment. That is, of course, unless the paladin is committed to chaos, lol – but then the question arises, is that paladin a paladin?
The other definitions in latter editions incorporated language that paralleled too closely the concept of the cleric. I’m hoping that in 5e, the paladin is placed squarely in the martial ranks and is identified by her/his commitment to good rather than their ability to act as a “symbol for all that is good and righteous.” Paladins committed to a general cause doesn't really "do it for me," but if there's an option for that, I'm cool.
Let clerics either wade into melee and, imbued with the divine power of their god, subject their enemies to the full righteous indignation of their god – or draw upon the divine powers of their deity through faithful observance of the dictates of their religion in the service of their fellow characters. That is where I believe the distinction between clerics and paladins lies: Clerics serve people (either allies, followers, or others – even when adventuring) through their faithful adherence to the dictates of their deity. Paladins serve an ideal, and while they, by extension, may serve others as a result, the primary focus of their actions is still placed upon their dedication to that ideal, whether it is simply a lawful good disposition (as in 1st edition) or a concept comprised of a number of virtuous ideals as in 2nd – 4th edition.
So, for 5e, or D&DNext, or whatever… I support a base cleric that you can customize as wanted. If you want a melee cleric with spellcasting ability (e.g. 1st – 3rd edition), then make these choices. You want a cleric that is more of a caster (e.g. 4e’s “invoker”), then make these choices. Want a little of both, well then make THESE choices!