Any chance a new category could be added? Caster level? Possibly Divine, Arcane, and even Psionic? I know we have Karma from a Strand of Prayer Beads, Divine Spell Power, Ioun Stones, Wild Mage, domains, and a few other items that boost spell caster level. It would be nice to see them listed in one handy-dandy place.
Updated my posts. lots of domain stuff.
Chromatic Dragon Domain- choose one
Metallic Dragon Domain
Not sure if it has been mentioned already, but Paragnostic Apostle from Complete Champion gives bonus domains, to a maximum of three in five levels.
The one thing I'd like to see added someday is a list of class abilities that change your type...