The OS often came with img.gz file, so unzip and
dd if=OpenELEC*.img of=/dev/usbXYZ bs=4M status=progress && sync works for me.
Not recommend testing libreElec or kodi liveusb on main computer, the root file manager may cause unintentional file delete. Keymap addon bug could make black screensaver uncloseable. Still, the confirmation dialog does decent job to prevent that similar to restaurant's tablet menu system.
Most addon has consistence UI navigation. Switching channels inside a addon is easier than to achieve the same result in mpv out of the box. Only some audio visualization addons work.
BubbleUPnP on android worked to browse or stream contents on kodi. Rygel is a linux package also make upnp possible, rygel.config in ~/.config. Use GUI or $rygel -UD and $rygel -s to start/stop app.
Usb gamepad works well out of the box in batocera. On kodi system settings' input, setup left direction buttons/joystick for navigation and a,b,x,y for play/select, cancel, context menu, tab.
Uisng keymap addon, here's my attempt on full size keyboard: left shift/delete to back, left alt to enter, windows key to home screen, q to settings, a to addon browser, z to file manger, / for video setting, numpad 8,9,4,6 to up,down,left,right. ./gen.xml