This is where I see there being an issue as well.

There's also potential for harassment due to people seeing opposing political opinions. As an example - My wife was once the target of harassment by a number of users on Reddit for days for warning people about an anti-abortion protest that was displaying graphic imagery. Much easier for those kind of people to coordinate harassment of others if they can easily see records of upvoting pro-choice or downvoting anti-choice posts/comments.

Hard disagree on the idea that upvote/downvote history being displayed constantly is a good thing - it seems like it's just inviting harassment. Should be opt-out at a minimum, and preferably opt-in.