I had my issues with it, for one the...
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...inclusion of the Zygons was beyond unnecessary, I'd have preferred to have them use of the evil things supposedly locked in the time war like The Nightmare Child or the Could-Have-Been-King or something like that
Hurt was fantastic and I'm sad we won't see more of him, but we got this performance and I think he stole the show completely.
Also the resolution opens up a ton of possibilities for the show but removes some of the motivation for previous episodes because all of the guilt and regret in the character is rendered pointless, it feels like a waste.
The special was still fantastic though, I absolutely loved it and I've watched it several times.
Perfection is a lifelong pursuit requiring sacrifice. The only way to get it quicker is to sacrifice the most.