First of all, I'm definitely surprised of what you guys actually did! You exactly copied South Park! Well except for the voice acting.. Although.. What truly disappointed me is this:
1.) The annoying - 3.5 seconds sound used for Dr.Who.. It was supposedly great, but it seemed overly used through the thing. It wasn't that funny anymore every time that sound play within the wrong place.
2.) Voice acting - Almost all of the voice acting was great, for a fan made that is! Yet one thing is a bit missing. It's Butters and Cartman.
=> As Butters isn't feel like Butters. And as far as I've watched it 3 times just to be sure. Butters only talked twice. (Continue on #3).
=> As for Cartman.. South Park isn't one of the best, without for Cartman's way of talking and his uncontrollable anger sometimes. He should've been exaggerating almost the whole random happening.
3.) Butters and Kenny, Missing? After 7:40 I didn't noticed them. As if they were gone in an instant.
=> After what Cartman did, and Dr.Who tried to changing Hipsters into Who's.. This seemed to be the law that doesn't involve a multi-universe. Meaning, Kenny and Butters were gone, most probably because of the plot-hole this fan made video.
And still... You all did great though, I'm quite happy of what you guys did though. Keep up the improvement :)