It's easy at my end. Watch what your kid does on-line (keyloggers work), don't watch pornography or buy porn mags that the little one can find. (I've never understood either myself)
I'm all for freedom of the press and what happens between consenting adults is not my business, it is my business when it comes into my house.
My wife and I have made it clear to our young one that porn is out of the mainsteam and he accepts that. I'm sure he will look it up but by talking about it openly on honestly, it's worked so far.
Me, I hope my kids never get exposed to that stuff. But in the final analysis, I'd rather catch my kid surfing porn than surfing Demoncratic Underground.
Your actions are good IMO. Parents shouldn't set bad examples when it comes to certain issues. We'll be bad enough examples on other things without meaning to be.
I enjoyed a good beer once in while, but I don't think my kids saw me take a drink more than a couple of times when they were young.