I agree with @Slak_Jaw about video mode - it’s for dj’s playing MP4’s onto a secondary display - and yup, it works really good. In case a track is audio-only, the selected visualizer kicks in automatically (in some cases - as i have had a blank screen on some days, still troubleshooting).
Now your request for the inbuilt visualizer to have some kind of shuffling methods or react to samplers, cues, etc totally makes sense too. Personally I would love it the change with every next track loaded (a basic function), or give the open for “shuffle all” and then later if it doesn’t make the app way too heavy they can implement the rest of the request.
