Shadow Word: Insanity was impractical for Shadow Priests, Maz the Hunter pet had a unique ability, Distract was useful for rogue sneaking, Warlocks had offhand weapons, Sentry Totem was removed, Amplify and Dampen Magic had specific uses, Shadow of Death was removed, Mind Soothe was target-restricted, Divine Intervention was removed, and Symbiosis led to balancing issues, eventually being removed by Blizzard.
Insights
Shadow Word: Insanity was a spell for Shadow Priests that removed a dot for single target damage in Mists of Pandaria, yet its impracticality stemmed from dot management issues, highlighting the delicate balance required in spell design for effective gameplay.
Symbiosis, a unique druid ability granting other classes special skills based on their spec, showcased the complexity of balancing diverse abilities across multiple classes, leading to its removal by Blizzard due to the challenge of managing 70 different spells for just one exclusive Druid ability, underscoring the intricate nature of game design decisions in maintaining gameplay equilibrium.