1) We currently have The Binding Coil of Bahamut as a raid and Crystal Tower is coming next. These two raids however are comprised of "floors" so they can and will be continuosly expanded in patches.

2) Yes they are indeed adding cosmetic slots sometime in the future.

3) Hardmode dungeons are to work exactly as you said. All dungeons will have a hard mode for them.

Other features you may or may not know: PvP coming (party vs party and then a whole zone for large scale pvp), housing with gardening and furniture, chocobo raising, the Golden Saucer as a casino, starting with 3 mini-games, roaming primals that when killed will grant the FC the option of summoning it once, new jobs are also a huge topic in every interview (they're thinking next class will be a stealthy, fast class for Thief and Ninja), add-ons

Can't think of anything else sorry ;P