It's just a pet peeve of mine when I post something that's simply expressing an opinion and it will immediately get rated down, without even getting a response in the thread.
A rating is basically a response. At your current postcount, while not unmovable, your karma will take serious pushing to really move. As such, you can safely interpret each post's rating as a comment on the post itself without worrying that it'll hurt you overall.
When you get a rate down, look at what you posted. Was the tone antagonistic or at least interpretable that way, which I saw as an issue in a couple of your rated down posts in the last couple months? That'll often get you hit. Was there a reason for the rate? If you can't find any reason for it and are happy with the post, you have to learn to ignore them. Unless you see a pattern of ratedowns where you can find no reason for it, you have to learn to live with them.
Unless you're willing to bribe Kao to camp your karma to perma guru. I hear he's charging $10,000 and a live baby wombat for that service.