Yep, if you want to go back to a medieval-style fantasy there more fixing to be done. I considered that in the beginning when starting DFRPG, as we had played a pseudo-historical crusades-era setting before, but ended up forwarding the timeline a few hunderd years to get a more pulpy/swashbucklery feeling. Noir does not translate to heroic fantasy that easily. The basic premise of having the city as a fixed setting does assume a certain level of civilization - pretty much any age after gunpowder weapons is easy to use, but I could see a campaign set in late Roman Empire as well.