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 button with the Toolbar
Fitts's law suggests keeping distances between small items smaller; I just dislike having UI elements in all corners of the UI.
add the same menu and sidebar between Prepare and Preview
so things don't jump around
The plugin is currently in the state of a proof-of-concept; there is currently no way to switch between the Recommended and Custom sidebar, and there is no way to change the materials/printcores in the sidebar. When all standard functionality is in its new place I'll post a prerelease here before publishing the plugin to the Marketplace. If you can't wait, you can check out the code here: https://github.com/fieldOfView/SidebarGUIPlugin
Things I'm considering:
integrate the action panel into the sidebar
move job name into sidebar
move standard view items into view options/legend area
The plugin is a spiritual successor to the Compact Prepare Stage plugin, though it was written from scratch with a different end-goal in mind. That plugin will not be developed further.
Update: a beta is available below:https://community.ultimaker.com/topic/26014-sidebar-gui-for-cura-40/?do=findComment&comment=229800