So what about Al, who lost his entire body? It could have been taken over completely by Gatelings. And Wrath wasn't created by Ed trying to revive someone, and yet he still got Ed's limbs.
Meaning, could another homunculus show up looking exactly like Al? (Could it somehow break out of the Gate without somebody attempting human transmutation, since the body is already complete?) Would it have any of Al's memories?
Would Al, after being restored, still have some Gatelings stuck in his body (if the body he gets at the end of the series is, indeed, the same body he had in the first place)? Maybe he's not entirely human/ has some weird split personality thing/ has evil tendencies because of the influence of the Gatelings?
When he 'disconnects' his soul in the movie, maybe that's b/c he has Gatelings helping to animate his body? Going along with that hypothesis- if he disconnected too much of his soul, would his body be left a semi-homunculus or something? Could the Gatelings take over?
Just presenting a few questions I asked myself. Any thoughts?
Warning: Some end-of-anime and movie spoilers