There is a lot of info out there. Maybe try to spend time researching each problem you have. Experiment.
I used to get migraines when using the computer early in the morning. The light from the screen seemed to pierce my eyes and slice right through my brain. I fixed that issue by wearing sunglasses but I haven't had that problem for years.
Maybe lighting and different screens / color schemes could help your eye issues. I can work on a computer all day with no problem to my eyes. But a black screen with white text really screws with me.
I will sometimes go out and work from up to a half dozen cafes / restaurants sometimes. That's expensive, but I consider that my office costs since I work remotely. I'll work at each location for an hour to an hour and a half sprint. I'll then walk to the next location. In a given day, I walk at least an hour. This gives my eyes more natural sunlight than I would get while cooped up in an office.
If you're working solo, then you don't necessarily need to be working full time. Work less hours and raise your rates. Maybe notch out time for certain types of work to be done with pen / paper and scan your notes. You could also spend more time meeting with clients and outsource / partner for some of your work.
I sometimes have issues with my wrists, but usually that's because I get into some sort of bad habit in placement / position. The soreness makes me realize the problem and adjust. The problem then goes away.
Ask 50 different people and you'll get 50 different opinions. Lots of different info out there. Just keep experimenting / researching to find something which works.
Of course, you could always go into something different, but nobody here can tell you what to do for a business to get into. That's also experimentation and exploration.
Either way you go. Experiment and explore.