Don't worry I gotcha. Lets jump into it. There's two methods you can try and they both work about the same
it's all up to you, now is a good time to remind you that you take all responsibility for what your doing
to your Nexus player.
So the first method is the no root method (which I give 75% of the credit to vlasp for a post he made). Very
simple install the launcher that you would like to use but more importantly it has to have the ability to be
set as the default launcher. Some launchers don't have this ability it's very important. Next connect your
nexus to your computer and open up a command prompt and type this:
adb shell pm hide com.google.android.leanbacklauncher
adb shell pm unhide com.google.android.leanbacklauncher
So the second method requires root.
First thing of course is to install the launcher you wanna use and update the leanback launcher (if you still
want to use it). Open up Es file explorer and mount everything as read/write. Now navigate to /system/priv-app
and delete the folder leanbacklauncher. Reboot and that's it.
HOW TO HAVE YOUR CAKE AND EAT IT TO
If you still want access to the leanback launcher and/or have settings in the app drawer download the settings
and/or leanback shortcut attached to this thread and install it. You'll now have the a settings and/or
leanback launcher shortcut in your app drawer.
Thanks to breakthecircuit and unvaluablespace for some great ideas.
If you have an icon that you think would look better than the ones included in these apps post them on here and
check them out. If they look good I'll switch them out
If your curious about the app-release it's just a standard launcher built from the sdk with some slight modifications.
<rant> marshmallow and android tv are terrible<rant>