It will be great if we can have three small columns on the tasks that show:
number of subtasks in the task
number of comments in the task
number of attachments in the task
This will help you to have a very quick idea exactly what and how much is happening under the hood of each project.
I am thinking that those three small, narrow columns are at the right of each task, just before or instead of the small arrow that appears when something is happening in the task.