I doubt that Dave would want to create custom architecture for a database consisting of a genus with only one entry, however.
I agree that hybridizer information is important in some cases. I want to know who bred my roses and clematises, but I don't care who bred my primulas, for example, and in the absence of a central primula registry or primula database, there's no simple way to obtain that information. I believe the hybridizer information is already part of the custom architecture of the pertinent custom databases. In all other cases, we can add the hybridizer's name in a comment if we wish.