One thing some people seem to be failing to realize is that if Father had not lost those 50 million souls, it would have been OVER. There would have been no way for the protagonists to win; even in his current battered state, barely being able to maintain "God" or "Truth", he is still repelling all attacks sent against him by multiple alchemists and various military personnel. The only reason Edward was able to do anything at all to Father was because of Greed's distraction and his incredibly focused, defensive state because of obvious reasons. I think Arakawa has done a fantastic job handling the ending, and nothing I've seen thus far has seemed like an asspull; all having logical explanations.
I don't think I'll ever have the same level of sheer enjoyment while reading a manga again. Bring on the ending.