If you would like to add some randomization to your tests, this is possible via the task-based suggestion method that appears when adding tasks to the test.
Task-based suggestion works by creating a pool of tasks that each test will draw from when its instance is created. This means that the more tasks you add to each set, the more possible combinations of tasks.
When adding task-based suggestion tasks, please note that if you add tasks with different task duration, this creates the possibility of having a different duration for every test.