A lot of people have already written about how brands should be posting content about lifestyle, not just using Pinterest as a product catalog. But just posting pictures about things from other categories relevant to your audience's life doesn't really make the most of Pinterest either.
When thinking about all of your content, ask these questions: Could this give people an interesting idea? Does it give them a reason to share?
People are looking for inspiration. They don't just want to look at pictures; they want to think about what they could do with things. Whole Foods and West Elm are constantly used as poster children for brands that are doing this right. Whole Foods gives people ideas on how to play and have fun with food -- not just eat healthier. West Elm gives people a lot of ideas on how to use and apply different design trends.
Think about what you're posting and whether it gives people ideas about what they could do -- and how they could bring content together in new ways. Your ability to inspire people to action makes you more interesting in their eyes.