If your product is brightly colored, draw inspiration from it. Use accents of the bright colors in your packaging, like this candy packaging. Each candy is a different color, and each bag uses the color of the candy on its sides and in the graphics. The line as a whole feels connected, but they’re just different enough that you can get the gist when a product is different than the next (without having to look at the candy).
Where food products are concerned, being able to see what it is you’re getting is incredibly important. Who knows what’s lurking in bags and boxes when you can’t see inside? These dog treats have a cut out window so you can see exactly what you’ll be feeding Fido. There won’t be any surprises once you get the product home, and you can tell that it’s quality just by looking at it.