Williams definitely does exaggerate the characters a bit, but the only episode that I feel had a major issue as a result of that was MMDW. Basically here's my takes on her episodes:
MMDW: Probably her worst; she modified the setting too heavily and didn't really handle the character interactions well.
Hearth's Warming Eve: I really have no real issues with this. The characters are exaggerated a little, but the plot of the episode was constructed so it made sense to do that.
Putting Your Hoof Down: Exaggerated Fluttershy a
little, but it's no more unbelievable than her breakdown in "Best Night Ever". Angel was an ass, but we know so little about him that we can't really call it OOC. Also, Iron Will was awesome.
Dragon Quest: I'm not a fan of this one, but mainly because of the fact that
They Wasted a Perfectly Good Plot. The characters were fine, though. They just spent too long messing with the teenage dragons.
Wonderbolt Academy: One of, if not
the best s3 episodes. My only gripe is that Pinkie was exaggerated a bit, but in light of how clingy she can be I don't think it was too bad.
Spike at Your Service: Spike was exaggerated a bit much, and the idea of AJ getting her hoof stuck on a pebble was ridiculous, but honestly I found the episode entertaining enough that I can overlook the characterization issues. Aside from the fact that Spike was way too clumsy, I thought his actions were mostly believable.
The TL;DR version is that Williams isn't
that much of a worse writer than anyone else; she just got off to a bad start and it tainted people's opinions of later episodes. There are only really like two episodes where the character exaggeration really caused issues.
edited 9th Sep '13 5:23:41 PM by JapaneseTeeth