I dont know if this project is still running but i would like to leave here an idea.
I would love the possibility to manually resize a dock panel (like resizing a window) at runtime. Basically, there would exist a resize border at the bottom of each panel that would allow a user to pull it and decide the height and with of a panel.
I have implemented the resize part, but i'm having trouble on how it would work for the other panels.
If you're interested, i would hapilly send you the code I have to resize.
Ah one thing. I'm using this in WPF and not Silverlight.