UPDATE #1
I did the same this night long. These are the data collected shown in a picture:
The high-resolution image is available for download from here
The green area is about night with Android Support running. While the red are is about using the smartphone in developers mode with a SSH connection active and some light administrative / investigation tasks plus sporadic use of UI plus 4G connection shared with the laptop and listening music in streaming from the native browser using BT earphones.
OBSERVATIONS (p.2)
As you can see the CPU usage is quite plain in the red are while jitters much more in the green area. Despite this, in the green area there is not an energy issue because the discharge rate is below 1%. This means that the smartphone can deliver notifications from Android apps without sensitive compromises energy consumptions. Great! 
Moreover, both the BT and the fingerprints reader was immediately available after having configured the Android options with Settings:System → Android Support → Show Licenses → (back). This might have correctly awaken or keep alive these hardware subsystems. A further investigation and test will be conducted.
IMPROVEMENT
I noticed that there are three settings about smartphone behaviour:
default- users customisations appliessilence- I expect that the no sounds are produced but musicdo not disturb- it is not clear for me this mode thus ignored
The #3 has a moon icon and suggets me that it is for the sleeping/night time. As thumb rule, the best user friendly interface is the one that defines behaviours in a situational manner like:
meeting, note barred- I expect that the no sounds are produced but musicsleeping, dark moon- it is not clear for me this mode thus ignored
The icons two icons complete the interpretation of the labels. During a meeting, I do not want that my phone makes any sound but streaming audio just in case the meeting is conducted using the phone itself. During my sleeping time, the same like in a meeting and the Android Support can be send to sleep if no any user-started app is running - in that case the user should be questioned about.
Warning: user sleeping mode is going to be activated but one or more Android apps are running, do you want close them and {disable, stop, suspend}¹ the
Android Support?
(Yes) (no) [_] native apps also [v] rember my choice
After all, if silence is required there is no reason to retrieve notifications until the next morning and moreover, the user might have shutdown all the data connections as well.
The situations model is much easy to be accepted because the users always know the kind of activity THEY are doing: it is the SMARTphone that understand the user will instead of being the user to have to understand the modes options. 
NOTES
¹ depending the implementation of Android Support supending and disabling options.