One thing I really want to see less of: Attempting to make magic a form of "science." (Sorry, Mr. Butcher. That's the one thing I dislike about the Dresden-verse.) Magic(k) isn't science. Magic is religion.
When magic is assumed as science, it also assumes that, like science, magic is dispassionate towards mythology, culture, and tradition. In short, the urban fantasy axiom is "Magic is the same everywhere. Culture and tradition are just 'flavorings.' " In the real world, that just isn't true. Not all magic systems fit into the Egyptian/Golden Dawn/Wicca template. (Disagree ? Try plugging in the ancient Chinese, Babylonian, or tribal New Guinean magic systems into that template.)
It seems to me that all modern urban fantasy takes a magic-is-science approach because it is dispassionate and, as a result, won't offend anyone. In short, magic has become politically correct.
If your character is a Catholic, give him a Catholic viewpoint and make his magic match it according to Catholic tradition; If your character is Wiccan, give him (or her) a Wiccan viewpoint and make his magic match it.
Sure, it takes a LOT of extra research. But it makes magic less homogenous; As a result, you gain real-world verisimilitude and lose that "I cast a ninth-level fireball. Roll your saving throw" feel.
While I can agree with you to some point, in that overly "crunchy" magic systems in fantasy novels can leave the sound of dice in your head. But I dont really think thats the case in Dresden. While sure, Harry personally looks at it as a Science sort of thing, its constantly pointed out that that is not how everyone does it, and in fact it almost a minority viewpoint; magic is too subjective to be considered a science. Michael uses magic, its just powered by God, wiccan magic practitioners can create holy water in their shrines, Etc. The only homogeneous things I can think of are the basic ways a human handles the energy (words/focii/gestures as mental insulation which is a common theme worldwide, the death curse, the murphyonic field, slowed aging) and some of the distinctions made about mortal magic (like how its the only thing that can canll outsiders, etc). Most of these seem to me to give a basic framework that allows all types of magic to exist. The problem about saying that the magic is a purely catholic thing or purely a wiccan thing is that people then ask why that one is real and all the other types of magic out there are fake? People (or at least me) like some sort of unified view of the world.
Aslo throughout Harry's association with Michael, it seems to me that his view of things is slowing swinging towards the faith side. Its one of my favorite continuing plots, the Harry's reconciliation with God.