Android One - Home/back button area sizeable (without shrinking everything)?

[sleze]

I can't find this anywhere else. The Home/Back/active windows bar actually takes up real estate on the screen. Is there any way to shrink it down (other than reducing the font size of everything)? I have it shrunk already using the font reduction but would like to shrink it more (and I may want to have other fonts the normal size).

I am using the Android One version.

 

[sleze]

Just to add to this, I tried installing SystemUI Tuner but didn't have any luck. Immersive Mode activated on the navbar was promising (basically, it hides the nav bar until you click near it like the minimize the Windows Taskbar works) but for whatever reason, I could not wake the phone up from sleep with it active (had to reboot the phone and disable it).