Short bio: Computer Scientist, FOSS supporter (read more)
Tux Machines (TM)-specific
I will look at few basic tools in both apps, the tools which one expect to be taught in the very first classes when learning one of those apps. I will highlight the areas where GIMP does better.
It may be trivial, but for me having the image size in the GIMP window title is useful, while the zoom level for Photoshop is not (as while editing you change that a lot) and redundant (is present in the status bar too). You have to go deep in the menus and dialogs to learn the image size in Photoshop. Image size is important info, is a parameter you optimize for.