Enchantment gives you very powerful tactical buffs.  Especially Haste and Divine Speed.  Haste, for a whopping 8 sp, gives +15 initiative to the target, often giving you 2-3 consecutive actions before the enemies get to go again.

Divine Speed gives +20, and when first applied, immediately triggers an additional turn for the target (so if you use your big-hitter troop, then cast it on the next unit's turn, but on the big hitter, it's like you used Command on them) /and/ refreshes all their ability cooldowns.  But costs 40 mana.

Haste alone is a big enough deal to make Enchantment incredibally powerful.

Destiny's Gift is also in Enchantment, and is so broken and hilariously overpowered that I'm kind of surprised that it squeeked through early access.

Regardless, Courage is universal, but I think Enchantment is useful enough just from Tutelage, Tireless March, and Wellspring. If Enchantment suffers from anything, I think it's having a ton of city enchantments that buff units, which you'll either love and abuse or just ignore.

Enchantment aside, 8 enchant spell books only yields 4 active unit enchant spells, some of which you get regardless, is kind of horrible.  We need a better balance between spells and enchants...  better yet, give some synergy to the two systems - it feels like the enchantment system is just something you tag on for the sake of having it.

Can't see it being worth not getting Chaos spells like Curse, or Direct Damage ones like Fireball and lightning. Haste is useful, but i get it every game with only 2 or 3 Enchantment spell books - don't need 8 to get it