As long as the normal smile and eyes are preserved, I am fine with facial features such as eyebrows, tattoos, facial hair, make up and such. Different eyes are fine too, like for asian clickies or ghosts. Upside down mouth is alright too, although I still dont like seeing a clicky being sad considering the amount of joy clickies usually bring.
It did start with lego like this too.. first they modified the original face with beards, eyebrows, eyepatches and such, with only women having a different mouth to indicate they where women. Later the faces got weird, took them less than 10 years to go from standard faces only to weird faces though.
Playmobil will hopefully not make the same mistake, they have been so good with it so far, no reason to abandon the friendly faces now. Especially since its not needed, playmobil faces allow for a lot more than lego, with earrings, attached beards and hair not being worn like a hat.