One of the not so popular opinions on this is that the only way to get the thrilling feeling back with open world mobs, and just to make the open world feel good again in general would likely be to get rid of flying. There is a reason i know the Bozja and Eureka maps so well, and its because i've had to scale every inch of those things. Same goes with FFXI. It makes having unique landmarks and a beautiful landscape worth it, because you actually have to traverse through it. Flying actually kills so much of what makes MMO's great, it kinda sucks.

That said, with the way FFXIV is designed currently, I'd be super annoyed and pissed without it lol. Like can you imagine doing those boring beat tribe fetch quests without the ability to fly and blitz the zone?