[teki4u]

Is it possible to install Kodibuntu, boot straight to the desktop environment and then start Kodi automatically? If I run Kodi on top of the desktop I can have services such as auto-mount running in background

Yes. When you reboot it will boot to the last session used. Kodibuntu has lubuntu and kodi sessions so if you remain in lubuntu and open kodi from there when you reboot, a login screen will show up, there you have to put your password and it will login to lubuntu desktop, unless you pick another session from login screen (kind of like lockscreen for Windows).

Would be better if you watch YouTube videos of kodibuntu to learn how it works.