Q's right. Nothing has been announced concerning the actual game content as far as being a remake of Ace Combat 2 is concerned. Nothing about the missing missions, nothing about any new features. Personally, I think this was the perfect opportunity for them to put in multiplayer. :P But yeah, nothing apart from amiibo aircraft, ? Blocks, and New 3DS functionality like the 3D and extra buttons.
about the "? Blocks", maybe if we shoot them, they'll spill a giant mushroom that will enlarge the player's aircraft twice as big and grant them double armor and Scarface One will shout in Mario's tone "YAHOOO!!" :P
Yes, maybe it is Mario who pilot the aircraft, and pilots ZOE are all Bowser sons! then instead of fortress intollerance there will the Bowser Castle where you have to enter and save Princess Peach! Please Bandai Namco, make it!!!! ^U^