After one week of test I still find this build very smooth and stable.
However I found that miui11 was more power saving efficient.
Based on stock rom, those one lost 1 or 2 hours of active use per day.
If somebody as solution like new kernel of something like that to improve battery I would be happy
[EDIT] If I force the Android battery saver mode to be active all over the day my phone can now reach the same screen on time than with miui. It's acceptable by waiting for better optimisation. [/EDIT]