My tabletop thing
Each tier requires a number of unlocks equal to all previous tiers combined. T2 requires 1, T3 requires 3, T4 requires 6, and so forth.
Magic unlocks spells and is a lot harder to traverse unless you started on it since you have to unlock spell proficiency per spell level if you don't start in it. Warrior and mage will have analogues- enchantments on weapons and tools are worthless in your hands unless you know how to use them.
My tabletop thing
Warrior and rogue, rather.
Also, path of Magic is how you unlock companions! Companions give you advantage in a metaphysical basic skill and can aid you in battle using your primary stat to attack but are otherwise extremely weak and fragile.