Perfectly reasonable since you have the materials and time, and mostly the inclination. I'd take it easy and work on a few at a time, not industrial scale. There may be some processes where working on several at once will be efficient. Depending on your own psychology, you may not want to have the whole set in view all the time, or that could be a motivation, depends on your mindset. The most demanding part I see is matching up the stems and stumels. That could take some re-drilling, sanding down, filing, etc. I think refinishing the briar will be rewarding, uncovering some lovely wood under the old finish and patina. Eventually show us the results! I'd work on several without major structural problems while you consider the cracked briar; I think it would be prone to burn through, but I'm totally guessing.