I really wish that there would be more wildlife in the game. This was talked about in 2012 on the forums and even had a dev responding to it. However, there is still a lack of background wildlife. I'm talking about butterflies, small birds (even owls at night coming to perch on tree branches, and they leave to go higher up during the day), even fish! Costa Del Sol's beaches just seems totally empty without having fish swimming around. Heck, make an NPC on the boardwalk in Limsa chumming the water and have sharks swimming around it. And sharks in Costa, too.
Edit:
Also have stray animals prowling the alleyways in Ul'dah. Make the game seem like it's more alive. FFXI added wildlife, why not this game?