Ive been searching to see if this may be a feature I am missing but being an adobe lightroom user they have a functional feature to access only one module at a time so that you dont wind up with multiple modules open and either having to manually collapse them or scroll down through many open modules to the one at the bottom.
It would be nice to have this option in SU where when you open one module in the tray any other collapses. This way you have your tray to the right and all options are always visible even when one is expanded if that makes sense?