Absolutely as Life State, Magic is not a skill that a human can easily pick up.
Unless we're talking parlor tricks. That's the only type of magic humans are capable of.
Actual Magic such as moving the heavens, elemental magic, Alchemy, Summoning, enchanting, etc are spells designed for sorcerers.
Magic as a Skill, should be exclusive among the different types of Magic Users: Sorcerers, Prophets, Mystics, Druids, Enchanters, Summoners, Alchemists, Wizards, Witches, etc:
General Magic Skill - Light (Sun Magic not magic made from necessarily Love), Dark (Shadow/Darkness Magic not magic necessarily made from Hate), and the Elements (Fire/Lightning, Water/Ice, Wind, Earth)
Enchanting Skill - Enchantments, to make oneself stronger in battles, protection charms, Upgrading objects, and bringing inanimate objects to life (enchanting Broomsticks to fly or clean the house, enchanting a common Mirror to become a prison for a sim of choice to become the Magic Mirror)
Alchemical Skill - Potions and Elixirs, Curses and Poisons.
Summoning Skill - Conjuring spirits and daemons, objects, Sims, loved ones and enemies.
Mysticism Skill - belief is a powerful thing, and to a magic User unlocking this skill will strength their magic, radically.
master this skill and you may even influence other magic user's powers.
Prophecy Skill - Close as one can get to omnipotence, Knowing the past, present and future, in clear detail. perhaps even too clear. this skill can be a burden, knowing all the twists and turns of life, in a single vision.
Transformation Skill - from Glamour spells, mice, fish, Insects and toads, to cats and dogs, Humans, Aliens, Vampires, Mermaids and More!
Magic should be a Biological trait built into the Sim's Genealogy, Like Vampirism, and Aliens, and Mermaids. Magic should be Genetically Dominant, so if a Human and a Sorcerer had a child they will definitely have a child with magical abilities, How ever What That child becomes is completely up to the player.
Like My Sim mother, Julia, is going to be an Enchantress/Prophet (Her powers are Light Magic, and wind is her element) and she marries a Human and has two Children, Her eldest daughter, Desiree is a Summoner/Druid (Dark/Light Magic and Water is her element) and her son, Mason (Me) is a Sorcerer/Alchemist (Light = Darkness, Fire is his element)
so the family magic is very diverse.
Not sure about Hybrids, because I feel like one trait has to be more dominant than the other
either you are a vampire with magical abilities, or you are a Magic user with Vampire afflictions.
A mermaid with magical abilities, or a Magic user with the power to Shape shift into a Mermaid.
A rare chance that child's Powers will be born dormant. Children born with magic, will appear "Human." Should the player choose they could have the child's powers awoken with Mysticism, they can... Mystics could also have the power to put a Magic Users powers dormant, making them powerless, or severe their magic users powers all together, making them Human.
I came up with this a long time ago, If a Player wanted to go about making their Human/Vampire/Mermaid or whatever, become a Magic User, they should have to go through the trouble of Hunting down a magic user.
Two options:
1) Befriend them and Choose the friendly Option: "Ask for Magic." if the oblige they will easily "bestow" their magic into you, as a gift.
2) Should they decline, the next option is steal their physical spell book, and read "The Spell of the Written Work." Doing so will have turned your Sim into a Magic User. However, this magic isn't your own, you stole the magic from another sim. It's sort of like Identity Theft. Your newfound powers, share the same magical fingerprint as the magic user you stole from. So you can undo any curse, spell, they've cast if you wish.
However if the Original Magic user learns what you stole their power, or learns you've abused their gift, they can "Revoke" their powers from your sim if they choose.
The Spell book an object as well as part of the Magic User's Interface, they are tethered to each other. Should your magic using sim be careless about where they place their spell book in the world (book Shelf, on the table) you then run the risk of any sim out their reading your book, and acquiring your power.
or even if they steal a magic wand, they will never be able to cast the same spells at the same power level as actual magic user can. No matter what level the Human is at in comparison a Magic User will and should always appear more powerful.
I believe there should be a challenge when it comes to magic and getting what you want out of it.
