This is very true.
Though GIMP also offers batch processing.
I use GIMP and sometimes Pinta when in a hurry. I am very supportive of the Pinta Project even if I admittedly do not use it often. But I do use it when it beats GIMP at certain tasks. For example, replacing multiple images - With GIMP you must export each image through a series of several whacks at the enter key over a pop up. With Pinta, select save as with ctrl+shift+s and it also remembers your last position. It makes doing that task much faster.
Gimp really is not difficult to learn. I realize that you omitted it previously but maybe it really is time you took another look at it.
I cannot think of a GUI tool on Windows that fits all these requirements either.
You may be able to work around the issue using autokey:
I use several hotkeys to enter complicated or lengthy terminal commands that I do not often run.