Next, write a simple HTML5 app for a television that will allow you to implement a 5-th item. The 3rd paragraph with USB it seems only possible on LG.
4th paragraph — I'm pretty sure it's impossible. If so, then see another option when buying a TV without Smart TV (much cheaper), put the default to display videos from HDMI. Then buy a cheap Chinese USB stick with Android, which when loaded will show the correct page (I think on Android it's already easy).