It seems that IGA didn't even had a 1999 game planned. He probably thought we were alright with just knowing that Dracula was defeated in 1999, which is weird. It would make a great game, even if the story is already "spoiled". Maybe they could make it a sidescrolling, old school Vania, like ReBirth (but with a little more effort put into it)? Making a Metroidvania or a more ambitious game would be problematic since there wouldn't really be any storyline twists and turns to speak of. I mean, there
could be , but the ending would be very traditional compared to IGAs other DS games. Which is fine with me, I just wanna experience that impossibly epic Dracula battle

His last form could be absolutely over-the-top and hard as hell. I wouldn't hold my breath for this to happen though...