Scimitars against the Dark and the magic in dream Al-Qadim campaign

I still have this dream Al-Qadim campaign I'd like to run, and reading through Spells & Magic lately, I've been thinking of any rules alterations I'd want to do. The key thing that sticks in my brain is those nifty alternate magic systems. Channelers, Witches & Warlocks, Alienists, Defilers & Preservers, Ritual Prayer, Conditional Magic... That could be game-changing stuff.

But I can't find any info on it online. Did anyone use these in play? Was one of the systems horribly broken or easy to abuse? Do they mix well in the same game?

The obvious first thing to do is assign different magic systems to different classes. Start with the priests:

Hierarchy Priests (Pragmatists, Ethoists, Moralists) - Ritual prayer. These folks follow the rules and gain their religion's power through rites and rituals. It may take longer to cast a spell if they do the right thing, but they can save some power by taking time to do it right and/or make a spell more potent with the right sacrifices or time.

Free Priests (Mystics and Kahins) - Conditional Magic. These free priests gain their power through investments and dedication. When they act in their deity's interest, their spells are quite potent. If they act against their deity's will, their spells are reduced.

Hakimas - Technically free priests, but neither of the previous magic systems seem appropriate. I'm leaning towards channelling, but it doesn't quite seem like they should be weakened by the cosmic insights they are granted. There's not a real established Hakima code to build conditional magic out of though, nor is there some Hakima rite to base ritual prayer off of. So I'm a little stumped.

Moving on to the wizards, its also nebulous here. I'm not sure if its unfair to have two types of priests use a different system than wizards, but there's baggage on a few of the ends.

First off, channelling seems reasonably appropriate, even if it were to be shared with the Hakima. I want to keep the Brotherhood of True Flame in the setting, others are so minor it's hardly important.

Second, either warlockry or alienism seems like it could be grand for the setting, but they don't fit with the Brotherhood of True Flame. They'd be great for a Scimitars Against The Dark type game though, and alienism fits the sungazer wizard kit in that Scimitars.. article in Dragon Magazine. But in a world where magic is gleaned from demons or the dark between the stars (or monsters that existed before time was?), where is the role for the Brotherhood? The sword-and-sorcery that I've read generally eschews wizards' guilds because wizards are power-hungry madmen, so maybe alienism isn't the worst. Warlockry kinda steps on the Sha'ir's feet though. Also, alienism really would force a Scimitars Against the Dark type game where I'm not 100% sure that's what I'd be into.

Speaking of the Sha'ir, even if Alienism is adopted for most wizards, alienism certainly doesn't fir the Sha'ir. Then again, the sha'ir also has a unique magic mechanism, so maybe an alteration there isn't needed after all. Though channelling would be fitting, it would just hinder the Sha'ir more: they're already pretty limited in terms of spells they get to cast, and channelling wouldn't really limit the Sha'ir much because they'd be resting a bit while their gen fetches a new spell anyway.

Then there's the Rawun. Bards are spellcasters in AD&D, so what's their magic system. And there's paladins and rangers too, but I suspect paladins could be ritual and rangers could be conditional no problem. But bards get a good number of spells. Should every rawun go bad from learning cosmic secrets? Probably not. So I'm tempted to give them channelling like the Hakima, but that seems crappy too.

Best case thus far, I'm just doing stuff for priests other than the Hakima. Maybe its not worth it after all. Or maybe channelling can be just used for the mages (not sha'ir), bard, paladin, ranger, and hakima. Alienism might really shake up the setting a bit (what if you eliminate non-free priests as spellcasting options?), but it might do too much.

The other major problem here is these variants are only applicable to an OSR or 2nd Edition game. This would majorly impact the balance of things in 5e. One reason, I suppose, why I like how older editions are still more customizeable.

Al-Qadim 5th Edition Patch: Sha'ir

Still a bit frustrated with adapting things for 5th edition. While in my Hakima musings, I said that the ha'ir and warlock were an obvious match, on closer inspection this isn't really true.

Thematically, the Sha'ir had lots of powers related to genies: identifying their works, calling upon them for aid, imprisoning them, and traveling to their realms. The warlock, however, tends to have powers that curse, blast, and befuddle their enemies and expand their senses. The Sha'ir had no powers of his own except for dealing with genies: he gained power from his minor genie servant. The Warlock is granted lots of these curse, blast, and befuddlement powers that might not be the most potent, but are easier to regain than wizard or sorcerer slots.

So, on the surface, it looks like the warlock is a great match for the Sha'ir: reflavor the Fiend to the Efreet, add in the three other elemental genies (Djinn, Marid, and Dao) and you're set! But does it really make sense for a Sha'ir to be hexing people or calling up his pact weapon? So its not just their spell list, but also the invocations, patron, and pact boons that are a bit iffy. I'm now less sure they're such a great match. Which isn't to say considering an Efreet to be a the Fiend a warlock makes a pact with isn't a great option, just that it doesn't seem to do the Sha'ir idea well.

Other options then... The wizard is exactly what the Sha'ir was not in 2nd edition. A Sha'ir tradition just doesn't seem like a great option, particularly since unlike a Sorcerer's origin feature, the wizard's tradition isn't selected right away. So it can't be used to make the sort of small but radical change to the class that I'm considering for the Hakima.

Clerics, Druids, Paladins, and Rangers just seem like a no-go right from the beginning. The bard has inspiration, song of rest, jack of all trades, and the like and this is before they choose a college at 3rd level. So meh. Likewise it's hard to imagine building a Sha'ir out of the fighter or rogue (despite Eldritch Knight and Arcane Trickster), to say nothing of the barbarian or the monk.

This, oddly, brings us back to the Sorcerer. Could there be a Sha'ir origin for the sorcerer? The third edition adaptation for the Sha'ir used the sorcerer as a frame and tacked the Gen servant onto it. Why do I keep coming back to this class that I don't like? I guess it has the fewest backed-in assumptions. Plus a first-level choice point that will let me really mess with the class without being too athematic.

So a Sha'ir is born, not made. He is a charisma-based caster who uses his sorcery points and spell slots to cast spells fetched by his gen servant. I might be able to dig it. It still leaves open the similar yet slightly more sinister genie pacts for the warlock. I guess it would look something like this:

First level...
 - Know Find Familiar, but it only summons a Gen familiar. Can cast Find Familiar as a ritual as well.
 - Reduce your spells known by 1/2 (Round up, Find Familiar doesn't count for this purpose).
 - You can send your gen to temporarily add a spell to your list of spells known. You lose it when you take a short or long rest, send the gen for another spell, or your gen is incapacitated (do familiars get incapacitated?). Give the gen an appropriate chance to find spells. Spend a sorcery point for advantage on that check and/or to have it happen sooner.
 - You gain double proficiency bonus when doing social checks with genies or identifying their works.

At later levels...
 - Consider giving an ability to summon the Jann for aide, bind genies, travel to their realms, be lent another spell from a genie, etc. These powers are actually kinda wonky and long-winded in the 2nd edition stuff, but maybe they could be simplified. Alternately, a few bonus spells, perhaps limited to affecting genies might do (Banishment, Contact Other Plane, Dispel Evil and Good, Legend Lore, Plannar Binding, Plannar Ally, Plane Shift, Glibness, Imprisonment).

Makes total sense now.

So the Sha'ir would basically be a sorcerer with even fewer spells known, but one really flexible spell known. They could gain spells from other class lists though maybe arcane classes would be easier than divine ones. I'm digging the idea so far. This also puts some of the really thematic options into the Sorcerer. I think Ghul Lord is the next clear contender for a sorcerous origin (hopefully clearer than warlock = sha'ir). Hopefully I won't spot some crap that makes this a poor match.