Preferably, these custom fields would be unique to tasks when viewing from My Tasks or if viewing them outside of My Tasks the fields would be separated/collapsed in some way to show they were not associated directly with the project that the task was being viewed within. This allows My Tasks to be a unique experience while not adding clutter when viewing items from a different contextual lens (the difference between the work that needs to be done in a project vs the work that needs to prioritized by me)
For more details on this justification, please see this Forum Leader tip: 📢 Tip on how to organize your work in a variety of ways (My Tasks Filtering Workaround)