Opening Ishgard (story), adding chocobos (exploration) and low-level NMs (content). A boss fight similar to Shadow Lord to cap the initial story would also be nice.

But really, If Ishgard had been open at launch, I would have been happy. There's really no sense of progression through the zones now, and having a higher level city as a goal would alleviate some of that. Not to mention Ul'Dah is being forced to serve as the Jeuno type city now, leaving Grid and LL near empty in comparison.

Hopefully, before the PS3 release they'll open it up so PC players have somewhere to go before the flood of new players.