It seems to me that historics should include any daffodil that is either 30 or 40 years old (take your pick). The American Iris Society uses 30 years.
The only problem with this is that eventually the newer historics dominate the older ones. That can be handled in part by having them compete by decade. However, this does not solve the problem of picking the best historic entry.
At least in the south Beryl should be retired. It should be given its own section. It is always winning best historic in our area.