Header Rows that group and/or describe the rows beneath them are very useful (especially in to-do lists) but they could be better in a couple of ways:
1. Allow users to designate rows as 'header rows' that are exempt from conditional-formatting, auto numbering and date-created fields, etc.
2. Allow a line's postion relative to a header row to update or populate a field accordingly (or vice-versa). For example, items under a 'High Priority' header could automatically be designated high-priority in the priority column OR updating a priority column field as high priority could move the line to the appropriate section (useful in form submissions).
3. Allow users to FREEZE header rows. It would be great to be able to scroll down through a long list while still seeing the header under which the tasks are grouped. This function would be great for any row items with sub-tasks.
Bonus: Building this out, it would be fantastic to also have a 4th option for viewing task rows. We already have Sheet, Gantt & Calendar - I'd love a card or post-it view. This view could put row item cards (with selected fields, discussions, attachments and even subtasks) into columns that mirror these Smart Headers. Users could drag and drop cards into appropriate groupings.