Re: Inspiration from Renaissance Florence
The idea of gods working mainly through their servants can allow faith to stay very real in the world, while still allowing for powerful magic to flow from the fingertips of these servants.
It also works to allow godly magic to operate more invisibly through disasters instead of energy blasts. Not knowing for sure whether an event was god-driven helped to fan the fires of paranoia and faith. It also allowed people to seize power. In the end, it might not matter if magic is real or not in the world, just that the general populous thinks that it is.
The way I think I would play it, is that magic is real, but hard to generate and somewhat rare. That should allow both options above to work and still keep history relatively intact.
Pete