A coworker / project manager at the company where I work was looking at alternatives to Trello. Trello is great for small projects, but it becomes a headache for bigger ones.
- It's hard for PMs to see the overall progress and big picture stuff.
- Tasks always end up piling up in one list (like QA or On Staging).
- Developers or Designers creating their own tasks (the details) make the board messy (hides the big picture).
- Related tasks are not kept together. (If there's the same task for design and for development, those two cards are not kept together, even though they should be)
I started a designing a task manager that is structured as a nested list. That way small detail tasks aren't mixed up with core tasks, and the progress of the detail tasks bubble up to form the progress of parent tasks.