I know this thread seemed to have run it's course but I was never satisfied with the human class substitute for the Elf class and the other day I had an idea:
The Elf could be played pretty much as it is written in the rules if we call it the Diabolist (Carcosa already has a Sorcerer class) and give it a couple of weird tweaks.
Basically, these spellcasters have made a dark pact of some kind to learn their magic. Because of that, they cast in different ways from the regular magic users who learned it the hard way, so Diabolists can cast while encumbered by armour. They have a few extra-demensional entities "riding" their souls so they are affected by spells in the same ways as the Elf (immune to Charm and Sleep, no benefit from Bless etc). Also, the voices in their heads makes it more difficult for them to be surprised (1 chance in 6) and gives them a better search skill (which progresses as levels increase and more voices join in...). Obviously they have a Chaotic alignment.
All this is a merely a new explanation for the current writeup for the class. I think it would be fun to make changes to how they learn spells.
Because of how they originally learned their skills there is no guarantee the Diabolist knows the Read Magic spell. He would start with 1D3+1 random spells at first level.
A diabolist could still transcribe a spell from a scroll in the same way as a Magic User but it would take the spell level times 2D6 days because of their lack of discipline; it's just harder for them.
They don't research spells though. Each time a Diabolist levels he/she gets a chance to perform a ritual to learn a new spell. The DM may determine if the ritual has to be completed before levelling again or be lost. Personally, I don't see why they should have to do it right away as they'd have lots of good reasons to want to wait.
The ritual would be fast, taking level times 1D6 hours to complete. As usual the PC would decide how long to spend on the ritual before completing it. In that time the the PC won't know if he/she has attracted the entity so it is still as chancy as the method used by the Magic User. The Diabolist concludes the ritual by killing a sacrifice. The sacrifice has to be a least a kind of medium-sized mammal (like a goat or dog) to bind the entity. If an entity is bound to the Diabolist he/she then spends 2D6 hours unconscious experiencing horrific nightmares as he/she fights for control of his body and soul. The character has to save vs Spells. If he/she fails the save he/she is marked by the entity. Some change that identifies them as servants of Chaos. Something like horns, vestigial/useless wings, cloven feet, a random and unnatural skin colour, etc. Kev actually came up with a great table in his Class Adjustments thread that would be a fantastic place to start. Once the character wakes up, he/she can add one random spell of the desired level spell to his/her Spellbook in a mad frenzy of activity. The costs of the ritual and transcription would be the double what a Magic User would roll for transcribing a spell (ie 20 sp per hour of ritual).
Now just to add a darker element to the class, a human could be sacrificed for an advantage in the ritual. If a human sacrifice is used, the Diabolist either gets a +2 to the Save vs Spells or a second randomly determined spell.
To learn a specific spell or create a new one a human sacrifice would be necessary and would give no extra bonuses. The time to attract an entity with such specific knowledge increases the time and cost of the ritual. Going up to level time 3D6 hours and requiring 30 sp per hour in materials. DMs may require Con checks or Poison saves to for the character to stay awake long enough to complete the ritual. If the Diabolist falls asleep, he/she doesn't lose the one chance per level, but does need to start over with new materials (with the exception of the sacrifice, unless it escapes while the Diabolist is asleep). The DM could still require the save vs Spells though, as the current entities riding the character's soul take advantage of his/her weakness to mark him again.
It wouldn't take long before the character was wearing loose clothing, gloves and a heavy, hooded cloak. I wouldn't mark them at first level, but I would have other clues to how they are just a little off. Things like dogs always barking at them or horses don't like them (maybe add 1d6x10% to the cost of a mount to reflect the difficulty in finding one that will let a Diabolist ride it).
So I think that solves the human/elf class problem with a weird fantasy twist. Let me know what you think.
Here's the link to Kev's table I mentioned earlier: