I wonder if Miqo'te can purr

[Velox]

I'm not sure if, with those specialized vocal cords, they would be able to make the same range of sounds as the other Spoken races. I honestly don't think SE put that much though into it.

The extra H's we see in names such as “Bhee,” “Kuzh,” and “Pahsh” represent a slight hissing/spitting sound that is made when the name is pronounced by the cat-like Miqo’te. Many of the other races in Eorzea cannot accurately reproduce this sound, so the H's end up going silent when read (Bee, Kooz, Pash).

It would seem that, on a biological level though, Miqo'te vocal chords are fundamentally different than most of the other races for them to be able to produce sounds that the others are physically unable to. No different than a human trying to mimic purring but not being able to actually purr.

I think SE has put a lot more thought into it than you realize. :P