I would love to see them lower the threshold for down-voting. I've only got 200+ karma, and it's hard for me to get more. I can't be on here all day commenting, and being the first to submit articles. If I have something important to say, I comment, otherwise, I mostly consume. But that doesn't mean I shouldn't be able to download a comment I don't agree with or find offensive.
If I ever make a site with community comment contributions, and include upvoting, I would just leave downvoting out of the picture entirely. Etiher you do not agree and do nothing, you like a post and upvote it, or you report a comment in violation of the site rules. Downvoting just means dissenting against those you do not agree with rather than having a conversation about it.
You should be replying to the comments you dislike and state why, rather than just think hitting a down arrow is going to right all the wrongs with their statement.
It is the most infuriating thing to make a statement, have it downvoted, but have nobody say or argue why or against your points. The whole point of forums is discussion, and downvoting (especially when it outright removes comments) defeats the purpose.