I have been using the Arch Linux ever since it was recommended to me in Germany by somebody at the language meetup. I am kind of embarrassed, that I do remember him, but I have no idea what his name is.
AUR has become a place where I have been searching for programs not the the repositories. I guess like most of the people that use Arch. So far, most of the programs that I wanted were there, except a couple of python libraries.
Well, there is always pip for libraries, but doing some through pacman and some through pip seems to me like a recipe for a mess. And possible conflicts.
So, if possible, I have always tried to create the PKGBUILD file and installing it from there. But I never really put it in the AUR, mostly from fear.