you've done something wrong if your WIZARD has less sp then my CLERIC at lvl 13. My cleric has 1158 at lvl 13, maybe you need to take a look at how your APS are spread out and/or how you allocated your stats.
To MT: when a group of all squishies takes 25 min or less todo pop, i think most of the issues with caster balancing has been remidied.