My feeling is that there is so much confusion in daylilies by unregistered (seedlings) plants, that I personally don't think they should be in the database.
We could have garden names of unregistered plants - but who would fill in the information on height etc - there could be any number of plants that have the same garden name. If I use your example of the name Pink Lady - what if I call a 14" tall, 1-1/2" rose daylily that I don't know the name of or that has no name "Pink Lady" yet another grower has one they call "Pink Lady" that is a 48" tall, 14" spidery daylily that is such a light pink that it is nearly white. Then, which one is "Pink Lady" ??
Then, in daylilies, we have growers/sellers who put their own name on an old registered daylily to sell it. I know of one grower who did this and then mass marketed the mis-named daylily to nurseries and big box stores. Which name should it be under? I don't think there should be two entries...