Location-specific sound effects
I was just wandering around Ul'dah and it struck me how quiet the place is. What made me realise this all the more is that you pass by a fountain and you hear it, but you walk into a marketplace and it's dead quiet. What do you guys think of the idea of crowd noise? I think when you enter a library, it should be dead silent, sure. When you're in the middle of nowhere, absolutely should there only be the howl of a distant wolf and the wind. When you're in Limsa, seagulls should indeed be heard.
But in the marketplace of a bustling trade hub city centre? It should have the murmurs of many people talking! Even other cities, the markets themselves should always have a slight sound of people. You don't have to have them actually saying things, just a murmur, like the sound you hear at a busy shopping mall. It would certainly go a long way to making the world feel more 'alive'.
Likewise, in other areas aside from fountains there should be more specific sounds. Not just doors (urgh, doors can be annoying...) going to a place such as the miner's guild? Well, obviously you'll hear a slightly different kind of "bustling activity of people" ;) Walking by a chocobo? Random kweh!
On a sidenote, while I do have the music turned off which exaggerates this, it should be noted that I have turned it on for a while at the moment to investigate how obvious this is and am loving the carnival music at the moment! :D It should be permanent. Or has it been this way for ages? I swear the Ul'dah music was never like this before. :D