I wish there would be a log or journal for projects and goals. It would list all the events (like sub-task completed, added, moved, scheduled etc) and comments of the child tasks as well as comments to the project itself (there are no comments to a project or goal now. WHY?). Each event should include time/date, sub-task as a link (if any) and the text of change. The same goes for Goals. The idea is that each task, project and goal has its journal and comments, Goal journal includes all the sub-project journals and sub-task journals. Project journal includes all sub-task journals. It may be a foldable field on top of the page or not foldable at the bottom.
It will allow to track the progress and analyze things.
Anyway doit.im is the best GTD app today, thank you.