Since this got flagship chipset and good camera. i have some suggestion for zenfone 6. Some features that already exist on others device.
Freeform Windows (Android Q).
Bubbles chat when clicked then open medium size chat freeform windows.
Seamless transition between main and ultra wide lens, or at least shorten the transition between.
Smoother zoom.
Pro Video Recording on stock camera (yea i know there is open camera, filmora, etc. but the result isn't stable since this phone is lack of OIS, i prefer video mode on stock camera because the EIS so Excellent)
Seamless change between front camera and rear camera when taking video without have to stop recording.
Accent Color
Improve night mode? ( I am currently using Gcam Night Sight since night mode on stock camera suck in my opinion, sorry)
I'll be waiting for next Zenfone 7, I hope it'll be more mature than Zenfone 6.
Thanks!