It would be extremely helpful if I could say "OK Google" and issue voice commands without my screen being almost entirely covered by the white "Listening..." pop up.
There are ways to achieve that:
Using Google search widget
- If you have a Google widget, simply tap the mic and say "Okay Google, the window that appears is not covering whole scren but its almost half:
Customising window with third-party tool (XHalo floating module)
- Good news is if you have root (and additionally Xposed framework), you can install the XHaloFloatingWindow, pin the Google to Status bar and launch it fron there with a small sized window as shown: