I can't agree that Android boxes are "bad", but it will absolutely depend on how they are built and configured. The Nvidia Shield is an Android box, and it is outstanding. But it's more difficult to configure for playing media simply because there are so many options for player apps, and then the apps need configuration. Kodi is a great player, but the number of setup and configuration choices might scare off some users. And of course it also depends on what version of Android the box uses.
But the overall issue you have is you are using what is considered an obsolete format. Yes, there were some fantastic analog displays over the years, but they really can't hold a candle to a modern HDTV. And since the vast majority of the programming is now expecting a 16:9 display, getting a player to display properly on a 4:3 analog display is just going to get harder. I wish I knew of some perfect converter box, but I don't think one really exists.
You know, I don’t usually post off-topic and I know this thread is almost two years ago, but I have an M2/Sega Genesis Mini console (with 40 built-in games and 2 bonus games), released September 2019 and to my surprise, the Screen Settings on the console has two options to display the games: 4:3 pillar-boxed, or a full screen stretched ratio. The full screen stretched ratio, to me, is best for 4:3 sets. I also have a Yotocap HDMI converter which I connected the console to my old set through, which has the Zoom-out button where the outputs are; the converter can zoom out 6 times, from 98% to 92% of the image. I have the console set to display the games stretched to full screen, and the converter set to 92% of the image, to accommodate what the picture on the original Sega Genesis consoles looked like. Since the Sega Genesis Mini is only meant for HDTV sets, I know this will probably seem weird to you. Besides, I’ve actually had the console for two years, since the Christmas of 2019, which was only 2-3 months after it was officially released in stores. Along with the Sony PlayStation Classic (which is also only meant for HDTV sets), it was a gift to me from one of my uncles.
I’m into videotapes and old electronics stuff, including extenders, converters and analog 4:3 TV sets (which are obsolete these days), and Miss Bianca is my favorite character in Disney’s The Rescuers (1977) and its sequel, The Rescuers Down Under (1990). I am not a Roku employee, only a user like you. ~ Jordan
Roku Express+ 3910X