Anything spirit related is pure speculation because we don’t know what spirit weapons we are getting (except the three we already now all rites)
Note: Best in game, not in the lore, best class in the lore would be a mage born savant that knows 100% of everything (or a curse user savant that knows 100% of everything), and at Max level. (you are allowed to think in the future, but it’s the present that matters the most)
Still, mage is the best. It can get two magics (later three) and sick as hell ancients, I don’t see a warrior or knight able to do that.
That alone makes mage the best.
Warriors get artisan weapons that could have special uses while knights get a total of 6 weapons (3 normal, 3 spirit), the spirit ones which could have some ranged attacks like blasts, beams and leaps.
However, they aren’t magics. They’ll also probably be less cool. I dunno, I gotta push the mage agenda. I assume the magics will be rather gimmicky, moreso than anything we have in game right now or even future weapons. Magic has the most potential, after all.
Pretty sure spirit energy causes things to happen - you aren’t creating actual lightning, you’re causing lightning to strike. You’re not creating earth, you’re causing it to be shaped. I may be wrong, though. Spirit energy is confusing.