My english is very bad, let me explain:
1. http://i.imgur.com/92nCqEB.png
sure, you can change colors by yourself, or percent position, it's just prototype.

1. How many tasks complete / left
   http://i.imgur.com/utv6857.png

2. How many tasks per task or topic or total
   http://i.imgur.com/0w696uv.png

3. Task Visualizator
   Example: http://i.imgur.com/doRFLml.png

Okay, let's talk about #4 few more details.
We have some "tree structure", why not to visualize it by extra math at client part to view how many we done, how many left, where we have a lot of tasks, and how to see all "small details" in the project.

Example service: www.subtask.com

How it must works:
1.) Click "Visualize Project"
2.) Some magic
3.) We have three of our project what we can see