Nexcom VTC 6200 installing Android 4.2 or higher
I used to own a PC with that same CPU. It ran Windows 10 so-so, that is well enough and not too terribly slow. It should run Linux acceptably fast. Android should run as fast as Linux. I'm not sure why your Android experience with it hasn't been positive since Android is simply a different OS on a Linux kernel. You might try running a Linux distribution on it to see if your hardware will run acceptably. If you are still set on running Android instead of Linux, you can continue your efforts if you found your hardware could handle Linux.