Everyone seems to be suggesting UI modification, more content, fixing the battle system, etc. But is that what really sells a game? While it is important, i believe SE and its user base have overlooked the most important aspects of a successful MMO. And with that being said, here are my very professional and well-thought out ideas:
1. Release miniskirts, bikini tops and bottoms, corsets, pretty dresses, scene hair, and whips for female classes.
why?: Revealing clothing will work great in advertisements to attract the average male gamer. Further, school girl outfits and cos play special event costumes will appeal to many people who like anime.
On the other hand, girls will have the opportunity to dress up and make their girl characters pretty. What girl wouldn't want to beat up a squirrel in a princess dress or attractive corset? If the accessories in the game are made to look prettier, girls can accessorize as well (hairbows, those cute elastic shape bracelets, cute earrings, etc)
2. put in a love story!!! Make it epic and corny but cute. This will attract hundreds of teen girls. Make sure the guy is really hot. If the dev team is scared that they can't pull this off, using a vampire that looks 17 but is really 100, and a werewolf , is always a safe move.
why?: Girls love cute love stories. Don't believe me? Go to twilight movie premier. Some guys love it too. But point being is if you stick a long vampire quest line into the story a lot of girls will play just to finish it.
3. Allow in-game marriage.
Why?: this will increase in-game relationships and in-game drama. And drama and relationships gets people coming back because they want to be a part of it.
4. more cute mobs and pets and stuff!!
Why?: Who doesn't like cute things. Fluffy moogles should be active in cities. You should be able to get cute pets and have cuddle motions. like the more cute stuff the better.
So if SE wants FFXIV to be successful, i think these are the best ways to do it.
Imagine a FFXIV banner with a cute mithra with a whip and in a bikini fighting a dragon.... who wouldn't want to try that?
Or a princess elvaan falling for a vampire hume. scandalous!
Seriously though, i bet you if they implemented these things the game would probably take off.... I'm not sure if that's good or really sad.