Rest assured, I'm not one of them. Although I'm now working on my first one: Acacia.
I maxed one or two types of ampies on some girls, but Acacia is my first one to get the full three-type treatment.
Fritialaria & Alpinia: maxed on ATK ampies
Anemone & Helenium: maxed HP and DEF ampies
Once I finish with Acacia, I'm going to max Bonci and Snowdrop. But it'll be a while before I finish those tw, so I don't have any plans beyond them (yet).