I've licensed Adobe Creative Cloud (Photoshop and Lightroom) for many years but I enjoy GIMP now and then. There are some things that could be done only on it. For instance Fourier Transform (I needed that to remove the hexagonal background of a scanned analogue photo on an old photo-paper). This function runs on Photoshop but only for very small sizes. For the original 24MPix RAW photo I needed GIMP.
I will definitely check out the other two recommendations :)

By the way, if there were native Linux version of Lightroom and Photoshop, I would've switched to Linux long time ago... Some aspects of Windows 10 are simply annoying :D