Honestly, this list of features is really impressive, I'm really starting to see what made AmigaOS so special for so many people, and I'm a hard-line *nix gal. AmigaOS seems really unique, in that it's an especially lightweight, responsive, yet structurally clever and well thought through system. It must've felt light years ahead of everything well into the 90s. This is definitely making me want to upgrade my A500 to Kickstart 2.04 or 3.1 to get these features.
AmigaOS was far ahead of its time and really a treasure trove of cool features. Not just on the UI side, most of its contemporaries didn't have loadable and unloadable drivers, pluggable file systems, etc. It's amazing all this even worked without memory protection, but almost all of it did work.
I was a teenager at the time so I got to play with it when it was new. I had the privilege of learning how to code on my Amiga 500. Sadly it was in AmigaBASIC and later AMOS Pro (I even bought the compiler for that) and I never got to using real programming languages until the Amiga was already defunct. I find myself going back now, though, and admiring the OS interfaces in context with much more knowledge. The UI APIs were very lacking compared to today's toolkits, but for the time they were really next level.
Using the say command with the shell to have the Amiga 500 speak out the sentences you typed in was absolutely magical. The fact that this was just an add on to an already feature rich computer was awesome. PC users only gained this ability much later with the parrot function on the Creative Soundblaster which needed to be bought being extra expense for your PC.
I used to love this. I had some programming software, Amos I think it was called, everything I made had to have a talking voice in it, could even change pitch and speed. It really was amazing.