About the crappier character spells: monsters of course use them also, so while they may not be the best for characters to use, they help to make the monster spells that much more diverse and usually will work better against you, the player lol. Also if you were to buff them or change them to something 'better', it might suck that much more getting them cast upon you! So in other words, they might suck, but they do serve a purpose, albeit for the monster AI. 
We are born, live, die and then do the same thing over again.
