Would public moderation logs promote witch-hunting?

If by "witch-hunting" you mean greater scrutiny of moderator actions, then perhaps.

It's a trade-off between the integrity of reddit and the ability of moderators to manipulate their communities without interference.

And is there a way that a community could overrule a moderator that wouldn't end up falling victim to a tyranny of the majority?

Moderators would still have ultimate control over the selection of sub-moderators, deletions, bannings and style. The only difference is that their actions would become visible.

The obvious question would be, how do you determine what is sexist, racist, bigoted, etc?

Sure, it's a subjective decision, and that will affect the character of the subreddit, and the character of the community.

However, there are many subreddits, each with different styles, and that's one of the things I most like about reddit.

I enjoyed GameOfTrolls when it was in existence, but I would never let any of those guys into any of my nicer subs.

The thing I love (or loved) about Reddit is that any topic was up for discussion, and the ability to tolerate opinions you disagree with is really at the heart of free speech.

I love that too, and that is still possible in several places.

I don't tend to hang out in heavily-moderated subreddits.

I haven't visited that subreddit [FreeSpeech]

It's not really an active community, sadly.

However, I've always said moderators should have the ability to set clear rules and delete posts that are in violation of them.

I think that's fine, except in the defaults, which are likely large enough to have a measurable effect on people's opinions. I believe reddit should make the moderators of these places more accountable for their actions, or admit that there's no real way to tell if the defaults are being used as a tool of political influence.