That's an excellent point about the ramifications of thumbs on data base pics. For the data base, it's only logical that we should be thumbing the photos that depict the plant for identification and descriptive purposes, rather than just beauty. If that is not purpose of the data base, than what is it?
I agree with others here that photos of the whole plant and plant parts other than just the flower are needed in the data base. If I want to add a new pic to the data base, but it doesn't add something significant to what is already there, then I might hesitate to add it. But different shot angles, even of the same flower, for instance, can be very useful.
I would also encourage contributors to caption their photos with significant data, like if the pic was taken in the wild and where. I guess it's just me, but I am irked when people say they don't have any time to add a simple sentence that can mean so much.