I think a cash shop can be tastefully done. As long as it doesn't ruin the economy of the game. Features such as:

Private Housing floor tiles
Hair color/style change
Face change (maybe this one I am iffy with)
Chocobo feather dyes (to color the tips of your chocobo with)
Unique fireworks or temporary costumes (for when you have some stupid crysta balance of 10 or something)

These are just minor examples of what the cash shop could be like. Money for the company, satisfaction for the user and no complaining about how broken something is from the community.

Cash shops don't HAVE to have the 5 power ranger outfits or some crazy UFO mounts that you see elsewhere.

In 3 years time playing the game, maybe I might have the urge to have a new hair look or something. I'd gladly pay to have it done. Sometimes small things like this help refresh a game without having to demand more content. I know in 11 if I could change my head hair style I definitely would do so in a heartbeat as well.