Dockable Windows

Additionally to using a very simple design for navigating through different pages, I am currently using the AvalonDock library from CodePlex. Seems to work nice (even if I have some issues with some of the themes - it brings my app to crash during startup or after moving a window).
It enebles the GUI to have specific dock regions, where you can arrange document windows. Makes it way easier than using splitter controls inside a grid - they come for free then. The user can arrange the windows like he wants and even remove them from the position an put it on a different screen.
I think that gives an additional functionality and a good look too...

Pro:

• AvalonDock gives an easy to use addition to handling in page windows.
• WPFToolkit used as chart library instread of WPF 4.0 buildin charts (Toolkit is a bit more advanced featurewiese).

Contra:

• Another library to maintain and keep updated.