I couldn't place why the books seemed so "meh" to me when the prose was good and I pretty much liked the characters you were supposed to and disliked the ones you were supposed to. Then I visited the dresdenfiles subreddit and there was a thread wondering who would win between Harry Dresden and John Constantine. It wasn't even a contest for me on who would win. John would wipe the sodding floor with Harry every day of the week you'd care to mention.
After reading Hellblazer for over a decade the Dresden Files unfortunately pales in comparison. At least part of the problem is Harry's immense and growing circle of friends and at-least-sometime-allies (read: every time they need to be his allies). He just can't get into THAT much trouble when he's a spoilers for rest of series
He just has all the cards on his side, he has play dates, not life or death situations.
Contrast that with Constantine from Hellblazer as a counter example, John HAD a lot of people over the years, they ALL DIED. He got a lot of them killed, or worse.
And this is just a personal peeve with all serial fiction; stop having Harry just get knocked out by the bad guys. Jesus.