Ideas for the plan tab... (not in order of priority)
1. Activities dependent on other activities; both visually and for workflow changes; for example if an activity takes longer than planned, then the dependent activities can be pushed back more easily
2. The often suggested Gantt view
3. Better visibility into Activity notes; managing of activity notes (modify, delete)
4. Activity/Activity folder attachments; Plan attachments
5. Rollup of hours in the plan; there currently isn't a sum of hours
6. Task duration; in addition to level of effort
7. When multiple resources are assigned a task, be able to indicate the resources % of the level of effort
8. More reports
9. Better usability