I am a fan of short sprints — preferably weekly. The longer the sprint, the more likely we are to work on assumptions, independent of how many user interviews we’ve done. Working on assumptions (gutfeel, if you will) is a product feature fit lottery. You rarely win the lottery. Any new product feature should be broken down into, if possible, atomic units that fit into a single sprint and pushed to production, and at best, be attached to a customer-facing component. If you are ambitious, or perhaps this is just a fetish of mine, product marketing is closing the loop with a public “launch” in some capacity.