Trello vs. Planner - whats missing in Planner and what would make it better than Trello

Thank you Mike, yours is a really excellent list.  It well captures the frustrations I had trying to move my org to Planner (I gave up for now).  At mentions, notifications, lack of history, and poor or no integration with the other products in O365 were the weakest part of the system, for us.

A couple of my own peevs to add to the list:

• Per-bucket sort choices (sticky).
• Ability to config system to add new task to bottom rather than top of bucket (I actually wish there was a right-click menu with an "add task here" function).
• "Move to top" function for faster prioritizing.
• Custom filters and views.
• Complete and automatic history/activity log, on each task and globally.