When a class
focusing on physical DPS picks up new gear with strength or agility, both their critical strike chance and attack power
- and thus their damage - improve. But this isn't the case for casting classes - while intellect offers a benefit
to spell critical strike chance (though the number on this is a bit uncertain) and spirit improves mana regeneration,
there's not a similar mechanic available for spells. In terms of gear, I mentally consider an item with attack
power to be akin to an item with spell damage on it, for the appropriate classes. The issue, however, is that
attack power can also be improved by strength and agility, while spell damage stands alone. What this means is
that casters tend to give up stats for spell damage, whereas physical DPS dealers can pick up armor with stats that
also improve their attack power.
Is there a happy ending to this story for the casting classes? I'll give you a solid "maybe" - patch 1.10 introduced a new priest talent called Spiritual Guidance, which is an interesting answer to the continuing complaint of caster itemization. Spiritual Guidance is a 5-point talent in the Holy tree (you'll need to drop 25 points in Holy to max it out) that improves spell damage and healing by up to 25% of the priest's spirit stat. This is a particularly fascinating talent that transforms one of the weaker stats into a strong one and makes gear with only stats a viable option.
This makes me wonder if similar mechanics may be, in the future, applied to other casters - mages, warlocks, druids, paladins, and shamans - allowing them viable gear options other than pure spell damage. Thoughts, anyone?