I commonly have task lists that are nested to an arbitrary number of levels. In card view, you can filter tasks to level 1, level 2, etc. This isn't very useful to me. I think it would be far more useful to have a filter "include summary tasks (or not)". Since my actual tasks are always on leaf nodes of the hierarchy, by excluding summary tasks, my cards would display the actual tasks.
For the time being, I am able to accomplish this by filtering to only include tasks that are assigned to someone. Since I don't assign summary tasks to people, this accomplishes the same thing, but it is a less than perfect solution.