Android Auto 6.0 will most likely include background support, a feature Google has been working on since mid-2019. Google offers several preloaded images that can be activated right from the app.
For now, it seems that Google wants to use the same approach as Apple, which also allows users to choose a different wallpaper on CarPlay. This means that the search giant would not allow the use of third-party backgrounds, but would force us to stick to an image that is included in a preloaded set of images.
Google is also working on adding Google Assistant shortcuts to Android Auto, and this will definitely be useful for those who trust the assistant to perform certain tasks hands-free.
Best of all, shortcuts will allow users to create automations that are then attached to the home screen, so theoretically you can get Google Assistant to run a series of operations at the touch of an icon. Google Assistant routines are also expected to get to Android Auto to allow users to configure multiple actions in a row that can then be started by the assistant.
Android Auto 6.0 may also include minor improvements here and there, including a warning that VPN connections will prevent the app from running.
Several main devices will have their own dedicated icon on the home screen to quit Android Auto in an attempt to make the experience generally easier and thus no longer require users to get hold of the mobile phone to quit the app.
Android Auto 6.0 is therefore expected to go live this month, but a more specific ETA is not available yet.