Standard Premium Kodi feature tests would include (using a standard Kodi install direct from the Playstore)
1) Auto Kodi dynamic refresh switching to match a TV's refresh rate to that of the fps of the source video.
For a PVR capable - Internationally sold Media player running Kodi, this is extremely important because in countries with OTA DVB TV broadcast at 25/50fps you want to run the Android System Resolution at 1080p50hz for smooth video Sync, and then when playing video in Kodi. Auto Refresh switch to a corresponding fps rate to get the video sync timing correct for all other video content.
Otherwise, users buying this device for PVR use in 25/50fps DVB TV territories will have to manually change Android System Resolution/Hz settings each and every time they want to watch Movies/TV series in Kodi. Otherwise expect video, playback jitter and judder.
2) Correctly Synced 24p (23.976 & 24fps) video and also 29.97 / 59.94 frames per second (fps) support.
3) Working & tested Android IEC61937 Audio support for comprehensive AC3/DTS & HD Audio passthrough when using Kodi Krypton.
4) Android Multichannel PCM Audio support in the Android HAL itself for FLAC and AAC Kodi PCM decoded Audio output.
5) Deinterlacing testing to carefully look for Full Motion High quality deinterlaced TV when using Kodi PVR's. Very important for Fast actions sports.
I agree with @
nickr - all the Non Kodi related Android TV & custom PVR matters and enquiries should really be Answered over in your own forums.
Just direct users over there, particularly if you are running a custom Android TV ROM.
The Kodi forums are not meant to be used for custom ROM / Custom Android Apps / PVR support.