How much dexterity?
For most sorceresses, putting no point into dexterity is the best path for efficiency and budgeting. Dexterity is unneeded, as most sorceress dont need an attack rating, and rarely are in the front line of battle too often too worry about defence. The only help dexterity can do for a sorceress is help with block, but with around 2.5 points needed per level to keep block at a high level, its fairly expensive. This attribute can be ignored, though if you find you need to block, its ok to put a few in here. There is one item in the game that is sought after by sorcs and has a dex requirement, thats WizardSpike. It has a dex requirement of 75, which is fairly high, so its best to put points in dex to use it if you actually have the item already.