Not having actually run a game yet, I could be wrong here but...
Aside from making up NPC's on the fly, to deal with an unprepared situaton, I get the feeling that the GM's portion of the table could get very crowded once NPC's and their sheets come in to play. Is this how it goes?
Also, has anyone played the game without magic? What if Wanted to play a WW2 setting for example?
I usually just write NPC stats on note paper, and note their actions/allocations there too, rather than using tokens for NPCs.
Also, you could run it for non-magic settings, but you'd have to decide what happens with the setting power that comes with the magic tokens. It's an important part of the game, and I just don't think it would be the same if you dropped it,