Those hookers are a Mage's worst nightmare at endgame since they can easily get you killed by your own magic. Other than that, as much as Mage is weak damage-wise at low level, it still got many super useful utilities, one example being the stun from the fire book as you mentioned here. Early Mage is mostly a matter of how well you know the build and how strategic you are in using its skills. There's certain situations where a Mage wins over every other builds at low level when it comes to killing certain type of ennemies, like those tanky orcs for example:
If you have a good handle on all 3 builds; Physical, Mage and Succubus, then you can try your hand on a Mixed build (no personality) since it's a lot more efficient and flexible even at early human playthrough. The stun from the fire book can serve as an easy way to backstab with a dagger, or give enough time to cast juicing on the stunned target, there's tons of options you can choose when playing this build. Then again, it takes knowing all 3 builds, what traits to choose first, what items to prioritize, how to effectively combo all of the various skills from all 3 builds, etc to be good.
Talking about Big Mama...
