No one seems to have any qualms with the magic-user starting spells/spell choice...casting system or allowances...
So, let's talk Clerics.
Clerics need a deity. A god or goddess from which they draw their "holy (or "unholy") power and are granted their spells (prayers, invocations, what have you).
I would make it suggested in the Basic set that any pantheon be adopted for those DMs not interested or knowledgeable in world religions to create their own. Real world (Norse is very popular, as is Egyptian or Greek/Roman) or the 4e pantheon, Greyhawk's of Forgotten Realms'...my own campaign workd/setting of Orea is particularly thorough and evocative, if I do say so.

and available here in ENworld...whatever you have access to.
That said, for the "All Fours" game, I figured why not develop a religious system for the game world. All set and ready to use. (Besides the fact that deity creation is one of my favorite elements of world-building and comparative and ancient religions is something of a favored hobby).
So, naturally, in the All Fours game, it seemed a "no-brainer" to break up the gods and goddesses into 4 "teams"....The most obviously, likely, mode of doing this (independent of "alignment-based" gods, "good/neutral/evil", since alignment would be an "optional" element to play)...was to break them up intothe 4 elements.
"The Sky Gods" (Lord and Lady of Air)
Amgur "The Sky Lord": An "All Father" figure/"King of the gods" sort like Odin/Zeus guy. God of the Sky, Lightning/thunder, seen as the bringer/ruler of "Civilization", Light, the Sun. He sees everything that happens in the mortal world (so also a god of knowledge/information). Hailed the world over as the most powerful god. For those using Alignment, Amgur is the Supreme god of Good.
Holy symbol is a billowing stormcloud, often portrayed with lightning bolts coming from it or just a lightning bolt alone.
Anwyr "The Star Maiden": Goddess of Night Sky, the Moon (or "Moons" if you like for your world design), the Stars, astrology/astronomy, who gave navigation to mortals (for ships/seafarers). Anwyr has a "dark side" (when the moon is new) and in this guise/these times, takes on a more sinister/unknown aspect as goddess of Darkness and Magic, "Mistress of the unseen" and prophecy.
Holy symbol is a crescent moon in a circle of 4-pointed (for the 4 elements) stars.
Collectively, they are associated with the "good", beauty, information, inspiration and creativity (the arts), the colors of White and Grey and the season of Winter.
Their clerics are known as "Sylphs" among men, after the supernatural servants of the god and goddess.
"The Earth Gods" (Lord and Lady of Earth)
Bellafryn "The Green Lady": The primary goddess of the element, above her consort. A "Mother Nature" figure, reigning over Nature, green growing things (thus, the Harvest), and prosperity (even in urban areas, the acquisition of monetary wealth as opposed to crops).
Holy symbol is an ivy leaf.
Burgonis "The Antlered One": Bellafryn's mythical consort, lord of animals, the wood, the hunt, and the "wild" aspect of Nature. Burgonis has a "Trickster" element about him, taking on the realms of "luck" (as in needed for hunting), and is thus seen in urban/built-up areas as a deity of gambling/patron of gamblers. He is known to delve into the deep places of the world and so is attributed some sway in the "hard" elements of stone and the mountains, where Bellfryn's "soft" green aspect falters. This lends him some affinity for "secrets" and "dark places" that are often extolled/worshiped by those of less than noble purpose.
Holy symbol is a pair of antlers or deer's head with antlers.
Collectively, the gods of Earth are associated with prosperity (either through Nature or otherwise), physical pursuits (lust moreso than love), day-to-day concerns/trials (like the acquistion of food) as opposed to the "lofty" pursuits of the Sky Gods, the colors of Green and Gold and associated with the season of Summer.
Their clerics are known among men as "Keepers", denoting their devotion to Keeping the Order of the natural/physical world. For those using the optional Alignment rules, they are granted/associated with those of Neutral Alignment but often with a "good" slant.
The Sea Gods (Lord and Lady of Water)
Crashurre "The Lady of Waves": She is, essentially, a female Poseidon. There is a great deal of randomness to her attentions/affections. She can be the calm, gentle sea or the raging tidal waves and hurricanes (Crashurre and Amgur vying for control of the weather). Her domain is the water, the sea, rivers, rain...anywhere there is Water, Crashurre
"Is." Thus, she is warranted devotion as a Mistress of Knowledge and Information, though less so than Amgur. She is often associated with the elements of "growth", increasing power (the stream to the river to the sea), and vies for attention with Anwyr as patron of sailors, though let's navigators revere Anwyr without malice. She has a "secret" aspect about her, those things among her "hidden depths" that some prefer to Burgonis, who knows nothing about the sea. In her kinder, gentler aspect, she is the "Giver of Life" and "Keeper of secrets" (whereas Burgonis' secrets
can/might be found/learned).
Holy symbol is a cresting wave or multiple waves sometimes portrayed with a fish beneath them.
Clambesh "The Knight of Tides": The Lord of Water is attributed more account as a Warrior...he is forever in combat with the gods of Fire, to protect his Lady, Crashurre. He, also, may be perceived through the raging sea and great storms as he battles the Sky Gods to allow his Lady to control the weather over the sacred waters. He is considered a god of protection, a defender, stability (the regularity of the Tides, reigning in his Lady's chaotic impulses), devotion, and a patron to fishermen.
Holy symbol is a clam shell sometimes portrayed with a spear behind it (at a diagonal angle).
Collectively, the Sea Gods are associated with duality, stability (Clambesh) and/vs. impulsiveness (Crashurre), chaos (Crashurre) vs./and order (Clambesh), capriciousness, those that make their lives in and by water, Emotion instead of intellect (perceived as the purview of the Sky Gods), especially romantic Love (as opposed to the lust of the Earth gods), devotion (to another), the colors Blue and White and the season of Spring.
Their clerics are collectively known as "Undines", harkening to the supernatural/elemental creatures which are said to serve them in their palace deep beneath the sea. They will strive, always, to bring down/defeat/expunge the followers of the gods of Fire.
For those using the optional Alignment rules, the Sea Gods are generally associated with Neutrality, though Clambesh is often viewed as a "Good" and Crashurre as "Good" and/or "Evil" depending on her temperament and interpretation by the particular religious organization.
The Fire Gods (Lord and Lady of the Flames)
Damoter "The Demon Lord": Damoter is not kindly looked upon. He is the bringer of chaos, the Destroyer, domination, god of war and the bringer of pain, a lord of the Underworld (Master of those whose lives he ends), volcanoes (where/when Fire usurps Burgonis' Earth). He is also toted as the greatest warrior among the gods (next to Amgur, of course, though followers of Damoter would disagree and Clambesh strives endlessly to best him) and thus maintains a popular following among/is a patron of soldiers, mercenaries and warriors of all types, and those that make their living by war and arms. He is believe to be the Master of All Evil (particularly by clerics of Amgur, Anwyr, Bellafryn and Clambesh), and the Lord of Demons.
Damoter's holy symbol is a skull within a stylized flame with 6 points (one to burn each of the other gods of the other elements).
Delthainna "the Lady of All that Burns": She is the soot and smoke that covers the truth/reality, brought about by Damoter's flames. She is the goddess of shadow (cast off by the light created by Damoter's Ever-present Fire), corruption, temptation, lies, the mistress of disease and the undead servants which she creates from Damoter's slain enemies. To her is attributed the acquisition of power through others (in her own case, Damoter), rather than the gaining/striving for power, oneself. She was deemed, by Damoter, command over Devils, instead of the Demons Damoter himself prefers. Delthaina is more "appeased" than "worshiped". She has an oracular order devoted to the (keeping more than) telling of "secret knowledge" and thus is awarded some consideration as a goddess of prophecy. Assassins, Necromancers (regardless of their personal alignment) and evil thieves revere her above all others.
Her holy symbol is a stylized flame with only 3 points (presumably for/to burn the 3 other elements).
Collectively, the Fire Gods are attributed the realms of death, power, innovation (creating that which has not yet been, and subsequently using it up!), demons and devils, and those dark impulses from which most humans (and other races) strive to work against the colors Red and Black and the season of Autumn (when the natural world turns red and dies, bonfires are used in the Harvest festivals/holidays and burned to appease the evil that comes with the increasing darkness).
Their clerics are called "Reapers" in the realms of men and are often given a wide berth.
For those using Alignment in their games, the Fire Gods are almost always associated with Evil...if not "Ultimate Evil."
And there you have the gods of the world of All Fours...maybe we chould call it Quartem? lol.
--SD