I'm a good mixture of both. I don't think I could be a good parent if I didn't worry about my kids and their safety, health, education..etc but I would drive everyone crazy if I couldn't relax and have fun!!
My SO is a worrier. He can be very strict about safety to the point of driving me nuts. i'm more laid back. He's the younger of 2 kids, and i am the oldest of 5 kids, so that probably has something to do with our attitudes as well. I think we even each other out, most days. ;)