We don't know explicitly, but we can infer
People have a tendency to look at things like most High Fantasy settings. In most settings, like Warcraft, for instance, there are "two "types" of power.
Holy magic, derived from the gods. The Paladin and Priest.
Arcane magic, derived from magical energy. The Mage and Sorcerer.
That's a simplification of things (Warcraft has a things like Fel magic, Void, etc), but it generally is true. TES magic is a bit different, because magic to them is science to us. It's a tool, it's what creates the Mundus. It's raw aetherial energies warped into what the user wants. God magic and science magic, well, they are one in the same. Like thread can be sewn into different colour sweaters or or even different clothes, or maybe even something that's not to be worn! All comes back to the same thread used to make it.
So when you look at shamanism and spiritism, is this not normal arcana at its core? It's weaved differently, sometimes people like the Psijics weave it far far better than other people, but the essence of magic is the same. Is spiritism not mysticism? Is shamanism not destruction, alteration, or restoration? The Khajiit practice different things, use different weaves, but at the end of the day, is it not just a different coloured sweater? That sweater might not feel good when rubbed against other coloured sweaters, it might be made of a fundamentally different weave, much in the way Ayleid magic, a definitive absolute concept, is incompatible with Bosmeri magic, a fluid perhaps concept, as the tome Aurbic Enigma 4: The Elden Tree says, but does it not hold, at its very core, the same potential and power as all other forms of magic?
Beredalmo the Signifier wrote:
Next the fanglement: Anumaril brought forth Segment One among the roots and showed it to the golden nut, and this told an ending, so that the stone became a Definite Acorn. That Elden Tree would not walk again, but Anumaril yet had further intentions for it. Using his dentition as tonal instruments, he dismantled his bones and built of them a Mundus-machine that mirrored Nirn and its planets. And when he had used all his substance in fangling this orrery, he placed the segment-sceptre within, hiding it between the Moons.
Then he waited—but what he waited for did not eventuate, and perchance he's waiting yet. For Anumaril had hoped to convert Green-Sap into White-Gold, and thereby make the Heartlanders' realm anew. However, Anumaril did not know, and was not able to know, why his plan went awry. You see, Ayleid magic is about Will, and Shall, and Must—but under Green-Sap, all is Perchance.
Therefore, I would assume that the type of magic is not really relevant in regards to potency, rather that it is the individual skill of the user which decides to improve upon the magical base set by their predecessors.