Hello Ben
I haven't found a way to default it to my saved layout, which is a pain. However when you have XPression Open in either the Sequence or Layout view, you choose and move all your boxes around to they way you like it and then right beside the Dropdown where it says default, if you click that icon it will prompt you to save your layout. Choose your name and hit enter.
Repeat the process for the other area ie Sequence.
Hope that helps.
#XPression