Bard
Defined by: Music-based magic; social skills, thievery and deception; swashbuckling fighting style
In D&D: Bard
Examples: Elan
I disagree about thievery,deception and swashbuckling fighter style and even the bardic music.
Other variants:
Arcane Sage: Arcane lore masters
Divine Bards: Lore keepers with divine magic
Nature Bards: Lore keepers with nature/spirit magic
Skalds: Warrior Poet
Troubador: Roguish Bard
Archer
Defined by: Bow; Can be soldier type, wilderness-oriented, sneaky type or arcane
In D&D: Ranger, Fighter variant, Arcane Archer PrC, Elf
Examples: Thief PC game, Kagome (Inuyasha), Legolas (LOTR)
In D&D, the 3e martial rogue variant could fit
Barbarian
Defined by: Rage; big and tough; 2h weapon or dual wield; wilderness skills; light or no armor
In D&D: Barbarian, Warden
Examples: Conan
1. Conan is considered the quintessential 4e Fighter. Mearls based it upon him.
2. It is does not have to be rage. The official 1e Barbarian did not have rage as a class. It was simply a wilderness warrior with basic weapon: knife, handaxe, and spear + additional weapons and proficiencies based upon the home enviroment. The second edition had a berserker kit (and a non-raging barbarian kit) in the Complete fighter's handbook. A later supplement reintroduced the barbarian class and, again no rage.
3. One of the three musketeers was prone to rages (I can't recall which one)
Wizard
Defined by: learns spells from books; powerful magic effects; starts weak and becomes invincible; magic school variants
In D&D: Wizard
Examples: Raistlin (Dragonlance), Gandalf (LOTR), Black Mage (FF), Harry Potter
Gandalf was the equivalent of an angel. That is where he got his powers.
Often there is overlap with sorcerers in that they have magical bloodline that gives them the ability to cast spells, but need the training to do so.
Sorcerer / Witch / Warlock
Defined by: Source of power, either innate (dragon blood etc.) or outside (pact with dark entitity): spontaneous caster
In D&D: Sorcerer, Warlock
Examples: Hennet (3rd ed), Esme Weatherwax / Nanny Ogg (Discworld)
Not all witches make pacts with dark entities. Some are priests/priestesses
of "Old Ways" making pacts with fae or other spirits.
Druid
Defined by: Nature-based magic; summon animals; healing
In D&D: Druid
Examples: Merlin (Arthur legend), Druid (Diablo)
The D&D druid is an animist and more of a dnd construct
From the writings of Julius Caesar, we know the druids were:
1. Concerned with the affairs of the gods and the other world (i.e. they would be priests/clerics)
2. They were historians, teachers, scholars, judges in disputes and criminal affairs, astronomers
3. They liked riddles and enigmas
To become a Druid, you were trained as a bard, then an ollave (priest) all of whom were trained as bards. The final step to becoming a Druid was being chosen from the ollaves based upon your discoveries and insights.
Therefore, in 3eD&D, Druid might be better as a PrC requiring levels in bard, cleric and, possibly, wizard
For a different than nature priest, take look at the Mists of Avalon, the Once and Future King (and the sequel, the Book of Merlin). For rpgs, look at GURPS Celts (Steve Jackson Games), Nation book: Avalon for 7th Sea.
As of Merlin being a D&D druid, it does not fit.
In some tales he is of half-demon blood sorcerer in others he is a priest of the old ways. Depending upon source, he is portrayed closer to what 3e D&D would call a bard, priest, and or wizard: He casts charm, healing, illusion spells, polymorph others, polymorph self etc. He has the gift of sight (or divination spells) and, in at least one instance he is portrayed as a skilled musician whose performance is
I'd look at the works of both Malory and Tennyson, TS White's Once and Future King (and the sequel, the Book of Merlin), Mists of Avalon.
Monk / Martial Artist
Defined by: Melee combatant; Asian theme; mystic powers (Ki); unarmed; "monk weapons"
In D&D: Monk
Examples: Feng Shui RPG; Crouching Tiger, Hidden Dragon / Wuxia movies in general
I'd also add the martial artist priest
Defined by being holy men with priestly duties, dealing with spirits and skilled in martial arts
In D&D, the 3e OA Shaman (or a class variant that makes a few changes to be more divine than shaman (e.g., removing the spirit companion).
ex. Buddhist Priests, Shinto Priests