We already have a Dancer trainer. http://bulbapedia.bulbagarden.net/wiki/Dancer
And Businessman, well, kind of, if you count the Clerks. I'm quite sure Businessman was their Japanese name.
And we have actors/actresses, they only appear in PokÚStar, the Suit Actor even has a sprite of its own, so yeah. I think the Suit Actors are the only class to use the exact same sprite for both males and females too, even though it always struck me as more masculine-looking.
It's sort of weird how all musician classes so far seem to have been guitarists. o.o
Zombie Superhero Cosplayer Furry Crossdresser Barber Pirate Ninja (not counting triads) Super Duper Nerd (as opposed to just Super Nerd) Alien Space Spartan Soldier Astronaut Teacher (we already have school kids) Babies (We have old people, adults, teens, youngsters, and this gen introduced toddlers. it only make sense to go even younger than that)