Some on topic but differing options you might consider.
I used to enjoy the odd game or two, and participated in other computer related activities at home,. Photo editing among them. While at the same time I used to do a lot on computers at work... soon this all caught up with me and I had similar issues to yours. I started with wrist brace, and looking for better mice, but came across some other changes that were far more effective.
1. I learned to be completely ambidextrous with a mouse. I set up my work computer to be left handed mouse,. and that gave me my strong arm for gaming and editing at home. This is by far the biggest change you can make, literally cutting in half the amount of stress you put on your wrist.
2. I got a pen tablet for photo editing. I still use mouse for some tasks, but a pen tablet, a low cost small one like the old "Graphire" is a much better tool for most editing tasks, and is far easier on the wrist.