I really like your sprite work! I'm also a big fan of how you've kept the old school difficulty of classic Castlevania without keeping the old lives system. It lets you naturally set how difficult an area should be by how long/tricky the room is.
I like the whip and jump delay, but I think one thing you could do to make your controls more responsive is calculate your jump direction on the last frame of jump squat: I tested different inputs a bit and concluded that the direction you're holding when you first press the jump button is the direction you jump after the squat is over. This would give players a couple frames of input leniency before locking them into a potentially deadly jump arc, without losing the deliberateness of the controls.
I would love to see a more robust version of this, there's a lot of great work here!