Wow, this is pretty great stuff
The only thing I could see being a little chaotic is giving EVERYONE the power to add tasks and members. My suggestion is if there are chairmembers for each group giving THEM the sole power of adding things. This way, you won't end up with 5000 tasks that are generally the same with different wording.
Other than that, it looks great
And i might have to get that to help out 1089.
-Sara