Hi,
I've been a beta user since the beta started. There are quality updates but many improvements can be made to ZenUI which I'll mention here -
Icon Packs - First is the inclusion of icon packs support. ZenUI supports it by I don't understand why it was removed for ROG. It should be there as most people use zenui launcher because of gesture implementations in A10.
Lockscreen Fingerprint icon/transition - While most OEMs allow changing to different styles of indisplay FP unlock icons, ZenUI has only one which cant be obviously changed. This is a feature request to please implement more styles.
Better AOD - The current Always-on-display is barebones and just functional. There are 3 styles to choose from of which none of them have any customization. And the panel itself is very plain. It doesn't show notifications, just call and message count is shown with the battery. Another problem with AOD is that it co-exists with the Ambient display. So when you do get any notification, you get the normal ambient display notification, which is static i.e. you cant act on it. You can just tap on the power button to see the lock screen, which shouldnt be the case. So this is a request to add a better and a more robust implementation of AOD, similar to the likes of MIUI and other OEMs.
The dialer problem - The dialer although is a good native app, feels unnecessary to use over Google dialer. While Messages uses the Google app, why does ZenUI use its own dialer? But the problem is bigger. If you get a call when your device is locked, you simply cant dismiss it. You have to act on it to get it dismissed. But ideally, you should still be able to unlock the device and the incoming call should go to the notification tray.
Better theme integration - Although this is a personal opinion, as Google has started to implement a theme engine with accent colours and fonts, it only seems reasonable to have that implementation. And another solution can be to integrate an Accent picker right inside the device settings, rather than forcing users to install themes.
Random soft reboots - The device still gets random soft reboots while using.
Battery drain - Many users including me have been facing battery drains on the latest beta
ZenUI although is a nice UI with its stock like implementation, it needs a lot of polish in areas like these.