I don't know why staff's allowed, thus far, CW makeup for around the eyes, but not the eyes themselves. However, in the past Peka-Boo event and the one coming up, staff allowed for players to create official wearables included eyes and mouths. If staff feels confident allowing users to create eyes and mouths for these kinds of contests, why not put the same confidence into the artists to be able to make CW eyes and mouths? I'm sure that people, both artists and commissioners, would have some great ideas for them and artists that aren't site staff would know very well how they're to be properly positioned on the HAs.
The eyes and mouths that were made official items during Peka-Boo were very well made. I think artists have know very well what they're doing as they can do it well :)

I don't mind that they have limited such things. It makes sense, really, to put some restrictions. As much as I would love to do my own line of eyes and mouths.
However, I wonder if we could argue our way into doing eyebrows. Technically, they aren't part of the base. They can be painted, tattooed, taped, etc. We should be allowed to do eyebrows.