Not just ice line. Freeze drops enmity more than it does damage. Against certain mobs it actually rocks damage, but those enemies are few and far between.

Fire line will suck up MP faster than you'll do damage in a fight. Flare is self AoE that makes it bad enough, with a burn enfeeble.

Resonance, I don't even use. Increase range. Only good for enfeebles which are useless.

Of the abilities 8~/20 are useful: Dark Seal, Sanguine rites, Parsimony, Thunder & Thundara (Sometimes Thundaga) Chameleon, Second Wind, and Convert. I don't count fire line because it's only good on trash mobs. I am not counting trash mobs anyone with an aoe can take them out, and it's mp consumption on bosses make it a less effective way to deal with them.

That is less than half the list of moves, I call that a failure.