I'm working on a plugin that changes the new GUI in Cura to be more settings-centric by adding back the concept of a sidebar. If you can't get used to the floating panels in the new GUI, there will soon be a plugin for you.
While rearranging things into the sidebar, I am also taking the chance to rearrange some other bits:
move X-ray from the Preview tab to the Prepare tab
in my opinion it makes more sense to detect/show errors *before* slicing
reunite the Open butto