why shouldnt an archer use cure, I dont think that your idea of what classes should be, wouldnt be very entertaining, and is contrary to a lot of what the game said they want to bring to the table. Even FFXI had a decent amount of customization, and a lot of those combinations, while not great in 6 man parties, actually worked well in smaller groups.
I can see a certain job getting a buff to certain abilities, or a mechanic that enhances an aspect of play, like say rage mechanic for warriors, or a whm getting back energy for healing, but to totally destroy what the armory system brings to the table by pigeonholding everyone to a specific skill set, sucks.

I think you are the one who wants to destroy the foundation of the armory system. and if this was the case, why even have jobs, they cant enhance charachter uniqueness anymore than taking all of cross discipline skills out of the game.