Since this thread has been revived, I'll pile on another recommendation for
Krita.
While it really shines for drawing, it is also my go-to software for all my image editing needs. I ditched Photoshop several years ago for Krita. After becoming familiar with Krita, I'm never going back. Krita does almost everything Photoshop can and many more things Photoshop can't. Very occasionally, I'll have to bring something into GIMP instead of Krita (usually for some obscure task that Photoshop wouldn't do either).
Another advantage of being free, full-featured, lightweight, and cross-platform is that I can be up and running in under 5 minutes if I ever need to do any image editing on someone else's PC.
I honestly can't see the appeal of proprietary software like Photoshop when it has already been surpassed by free software in almost every way. Unless you have a very rare and specific use case that requires a very rare and specific patented feature without an equivalent, you really shouldn't waste money paying for otherwise inferior software.