Improvements for MS Teams integration
Timestamped Comments you can add comments to regular plans, but the ones in Microsoft Teams doesn't suport for adding comments.
Search: It would be nice to be able to search tasks within Microsoft Teams
Templating tasks: Trello allows you to template things like checklists so that common tasks can be created quickly.
Mentions: It would be nice to be able to @Mention other employees within a Task.
Just noticing the lack of search functionality on tasks in a plan from within Teams. I guess this stems from the lack of search functionality in Planner.