Given your background it should come to no surprise that it doesn’t really matter much.
That said, I recommend Arch with some caveats, mainly with regards to the “very little effort to start using” requirement. If you know how to follow instructions, it should only be about 30-45 minutes to install it. It will on the other hand fit your other requirements of good defaults and not shipping with loads of applications. When you install an app you will get that app and nothing else, and the defaults will either be exactly what the upstream defaults would be if you built it yourself or something very close to that. You also have everything available through the AUR, and after using it for years I’ve yet to run into an update not going smoothly.