KoFXII was an incomplete Nona nightmare of a game. But, on the plus side, it should be easy to fix. That there's a KoFXIII to begin with means that SNK aren't completely stupid and budgeted for XII not being a success.
The 480p sprites can't be helped but that's a minor problem. This is what MUST be done:
* 10+ new characters, new or old - I'd want Billy and Yamazaki but really anyone is fair
* At least ten brand new backgrounds as ALL of the ones in this game suck - with NO sped up looping animations cluttering the air
* A proper single-player mode with a boss and pointless dialogue - really, how long would it take?
* Recolor everything to not be Nona-brown - KofXI had awesome color
* Beef up the movelists of everyone - two moves for Mature is a ***** disgrace
That would be a good start. Remember, KoF took three games to get good in the first place so the first of a reboot can be excused. And it's not as if Capcom has made a first good game in a series between 1992 and 2008...
Of course, I'd see the entire series killed if it meant getting Samurai Shodown back to its 2D glory, but that's not happening now is it?