My feelings are actually somewhat mixed on this. To sum it up briefly, FFXIV to me doesn't stand out in any one area in particular, but what it does have that other MMOs (that I've played) don't is a pretty even consistency across the board.
Graphics? After playing Black Desert Online, pretty much every other 'modern' game looks outdated. Artstyle? Though this is a personal preference, I much prefer the ethereal world designs of Blade & Soul or Tera rather than something like Eorzea, a world that appears to be fairly grounded in reality. Yeah, I know, you've got a couple floating island areas, but that's got nothing on Tera's giant glowing pattern across the sky, to use one of dozens of examples in particular. Other people who have tried Tera will hopefully understand where I'm coming from. Character creation? Oh, don't even get me started. FFXIV is blown out of the water instantly by PSO2 and just about every Korean MMO out there. No contest.
Combat? Well again, this is more personal preference, but I much prefer action combat-oriented game systems like Black Desert Online, PSO2, Blade & Soul, Soul Worker, and more. I don't exactly find mashing out one button combo over and over to be terribly engaging. Eureka burnt me out super quick for that exact reason. I enjoy being fast and mobile and cleaving through enemies like the WoL does in FFXIV's trailers, but cannot be found in the actual game itself.
Story? Believe it or not, while FFXIV's story is several notches above standard MMO fare, I do not consider it to be the best story in an MMO. Blade & Soul's main story ending, for example, literally had me in tears. I also found that The Secret World's main story was more engaging and compelling, and Mabinogi's was fairly decent as well... though to be fair, nothing kills my engagement faster than spamming fake deaths over and over like FFXIV's writers seem to have been doing lately. It was old at the beginning of Heavensward, and it's no better now.
The thing is, while FFXIV doesn't really shine to me in any of those categories—along with having a stale content cycle, messy coding, and the ever-present Server Limitations™—it still remains my top MMO at the moment, and that's because it lacks the massive drawbacks that the other games have. Black Desert Online has fantastic graphics and combat, but has barely any endgame, heavy reliance on unbalanced PvP, and greedy devs intent on bleeding the playerbase dry. PSO2 has tons of content and amazing character customization, but the content cycle was too fast for me to keep up with, and they've been gradually moving to more of a mobile game-style payment system, which turned me away. Blade & Soul has great combat, stellar PvP, and a world design to die for, but it lacks substantial endgame content. Though these games' individual aspects beat out FFXIV, FFXIV remains the most consistent of the lot, whereas the other games have huge negatives to outweigh their huge positives. And that's why I prefer FFXIV at the moment.
