There comes a time when we have to change.

It's just a thought but if you do want to paint using fine brushes, I have adapted them by pushing them into a small piece of foam rubber so my grip can be more relaxed.  This might work for when you want to add a little fine detail.  These things are sent to test us; I hope your consultant can help.  I'm having eye problems currently and should try to sort them out. Btw, I do like your painting of Malham Cove, it has a special place in my heart as we often visited as children.  Years later, my boyfriend and other members of their caving club actually abseiled over the top of the cove right down to ground level.  Not something I would recommend watching from the top!