2. Can some of the sidebar widgets be collapsed or even removed to help reduce overall noise?
3. I'd suggest moving the "Activity Update" panel above the "Tasks" panel, just under the user's name and profile photo, since updating status is presumably the primary goal for most users.
4. The "Edit Profile" button below the primary navigation could be removed and replaced with a hover invitation link next to the user's name or perhaps by clicking the profile photo, further reducing the number of elements competing for attention. On a related note, could "My Tasks" be removed since it is already displayed prominently in the main content area?
5. On "Case" pages, the actions displayed below the primary navigation are difficult to visually scan and parse. This is compounded by the fact that unrelated buttons share colors, making it difficult for the user to create a mental model and anticipate expected behavior. A dropdown menu of options might be more appropriate to show all available actions in this case, and would further reduce overall noise.
6. There is another usability issue to consider with the buttons placed directly below the primary navigation bar. If I run the cursor too close to the top of the target area for the buttons, I can easily trigger a dropdown hover from one of the primary navigation menu items above it. That could get frustrating in everyday use.
Have you done any structured usability or task completion testing with real users yet? Check out Steve Krug's book "Rocket Surgery Made Easy" for some ideas there. You could also gain a lot of inexpensive insight using services like feedbackarmy.com, userfly.com or loop11.com. Hope that helps.