Not free but rather cheap (around 30€), but you should look at the Affinity suite (Photo in your case, and Design if you are at some point interested in vector

Not free but rather cheap (around 30€), but you should look at the Affinity suite (Photo in your case, and Design if you are at some point interested in vector drawing). I made the exact same research a couple of years ago: I couldn’t afford Adobe’s products and wasn’t feeling Pro enough to use Photoshop nor Illustrator. It’s snappy, easy to use and has lots of features for me not to feel constrained whenever I use it. Best software purchase so far.