Recommended Sword Enchantments
Flat melee damage boost - the core offensive enchantment. (Sharpness, Smite and Bane of Arthropods are mutually exclusive.)
More and better mob drops - essential for farms and endgame economy.
Full sweeping damage on crowds; pairs perfectly with Sharpness for mob farms.
Durability lasts ~3x longer on average.
Repairs with XP - effectively immortal when combined with Unbreaking.
Optional: cooked food drops and extra damage; skip if it conflicts with your farm design.