Cabalist team leader Gtss posted his "Cablist 1.64 Report and Feedback" over on Camelot Vault's Albion Mage Professions forums:

In the previous report, you asked for feedback on the request for higher spell levels, specificaly, a Level 49 Base Dot and a Level 50 base Lifetap. Currently, the Levels are at 44 and 45, and the class is the only caster class that doesn't have access to at least some version of Level 50 baseline damage. On a Level 50 Player or Mob this means an extra 3 to 4% resist rate, but with mobs several levels over the Cabalist, that 3-4% is much much more important. The other issue with resist rates is that normal DDs are coded to specifically give the caster more of a chance to hit mobs over Level 65. Dots, Lifetaps and Debuffs (the only spells in the Cabalist arsenal), are not coded this way.