I have two sets of hickories but am reticent to use them. I fear they might break.
I had that same fear for quite some time. When I first started playing I was paranoid of breaking a shaft due to a hard range ball or a mat. Now I know better.
Yes, over my 12 years of hickory play I've broken a few shafts, but much less than one might expect. The key is ensuring the club is properly prepped before play. This would include evaluating and potentially refinishing every shaft before play, and removing and re-gluing every head. An old and brittle shaft will break eventually, but often a shaft that looks bad just needs a light sanding and a new coat of shellac to gain a new life.
A good hickory shaft is just as strong as graphite and can hold up to quite a bit of abuse, you just have to be willing to let the club do what it was designed to do.