I'm starting to think the way to go isn't set stories in the sprint at all. There's a refined backlog in priority order. You grab one, do it, grab the next. At the end of the two week period, you can still have a retro to see how the team is doing, but don't worry about rollover.
Alternatively, don't think of Agile as a set instruction manual, but rather a group of suggestions. Have problem X? Solution Y worked for many teams, so try that.
This is what I always say. Put the tickets in order and we'll do them.
Management always pushes back.
Pro tip, if this happens to you split your tickets up into smaller chunks! It has two effects:
One is that you will see progress from one sprint to the next, even if it's 1 story point at a time.
It also has a psychological effect! If you're like me you will avoid the huge, nebulous tasks. But if it's something manageable with a defined start and end, you will do it. You could probably even schedule it.
