What is considered the best CV hack, Jorge?
I still think nothing can ever beat your cancelled III remake
Unfortunately that awesome looking Simon's Quest hack seems to be on hiatus. But the music coder for that game, Optomon, is making a CV2 hack of his own that changes graphics, mechanics, and a ton of other stuff to make it into a completely new game called Pyron. The end result isn't really a Castlevania game but it's still damn impressive.
Pyron (Gameplay)