I think most fictional magic operates along non-Vancian lines.
I would say that- but for a very few exceptions- determining how magic works in a work of fiction is more about game design than the way the writer thinks about magic's mechanics...if the writer has done so at all.
Two Notable Exceptions:
There is one series of fiction (I
think it's Gordon Dickson's
Dragon & the George books, but don't quote me on that) in which magic users have "
magic accounts just like checking accounts. You have a balance. You subtract by casting. You add by doing other things. But your "experience level" has nothing to do with your balance. It is entirely possible for a "noob" to have a whopping huge account, and a learned Mage to be stuck for a while with nothing.
Larry Niven's
Magic Goes Away stories are a classic mana system. Mana powers magic, but it is not a personal resource in large amounts. It must be gathered from objects & creatures in the caster's vicinity. And it is amazingly precious- it doesn't recharge on the time scale of human lives, so once an area is depleted, it is devoid of magic for
aaages..
The former system looks like a natural for spell points. But by it's nature, SPs modelling this system
exactly would be allocated in a somewhat random fashion, leading to all kinds of balance issues. A skills based system- or SP/skill fusion- might be better.
The latter was actually modeled well in the original Dark Sun's Defiler magic- a Vancian system. Using a SP system here could lead to very short battles, since the first caster to get a stranglehold on the local mana
cannot lose...because by doing so, he simultaneously powers his own magic while preventing others from powering theirs.
But other books?
Why do these elves in this series cast levin bolts effortlessly? It could be because thats a natural to them as breathing. Or are they tapping into an external source? Or are they flinging about their personal life force?
Unless the author tells you, you're projecting your personal perspective as a gamer or designer onto the fiction.