A thought occurred to me.
The difference between PCs and NPCs in the DFRPG (as far as we've been lead to believe) is their Refresh rate. If you have 0 or lower refresh rate on your Fate Points, you're an NPC.
But, with advancement, your Refresh Rate can increase.
So it's possible to, as the game progresses, play even more of a "monstrous" PC than when you started out. If the whole group has advanced to say, equivalent of gaining +3 refresh, then you could play a creature that WOULD have a refresh of -2 (hence, having a Refresh of +1 and be equal with everyone else).
Or if nothing else, your White Court vampire or Ghoul or whatnot that DID have a 1 Refresh now could have a 4 refresh, and be even MORE close to the human side, even MORE in control, as opposed to getting weaker as it advances. Granted, you can't do anything new, but you can likely have more "room to work".