Yes, I know snapseed is a mobile app, but that’s the kind of simplicity I’m looking for. Pre-made filters, an auto-fix button, adjustment sliders, etc.
I have image toolbox on mobile and even that’s a bit over the top with option (and I still haven’t found sliders for brightness, contrast, saturation, shadows etc in that maze).
Linux or Windows programs are fine, I run both.
Check out Shotwell. Its editing functionality sounds exactly like what you’re looking for, although it is designed for managing a library of images videos.