If you don't yet have a big enough audience that is going to get enough responses from a survey, then i want to encourage you to go to someone else's blog or facebook page. Looking in the comets of their social media platforms can unearth a gold mine of topic ideas. You're not there to copy their content, but to find inspiration for what you can create with your own spin on it. I love what mark twain said about new ideas. There is no such thing as a new idea. It's impossible. We simply take a lot of old ideas and put them into a sort of mental kaleidoscope. And we keep on turning and making new combinations indefinitely.