The parts about no complicated file formats, ease of backup, keyboard only, fast, easy to use, text only, etc. strike close to home for me because this is what I also desired, to the point that I've written my own program to keep various notes. It also had to be portable (Windows and Linux) because at the time I had another weaker laptop that had to run Fedora and I wanted to use it there too. I just couldn't find such a program, everything was bad, not portable or 'rich' (aka images, styles, etc. aka needs mouse or has a complex file format).