I just finished your alpha and its a lovely game so, have some notes.
Being locked out of taking any action while in another action (jumping, falling, whipping, parrying) feels awful and is probably a big part of why I felt the game wasn't consistently responding to my inputs. Animation cancels for whip and parry would be nice.
The major other issue I had with the game not feeling responsive to my inputs was jumping: when you run off a ledge in real life you obviously can't jump on thin air, but in video games, one of the things that makes platformers bareable to play is a bit of coyote time, so players can jump as a frame or two after they're off the ledge. This just makes the game feel more responsive because when your platforming and you press the jump button but it doesn't jump, it feels like the game ate your input.
Lastly, during the second boss fight's second stage, its possible for her to spawn on top of you while preparing her impaling attack (if your standing all the way to the right. Having a check for that and spawning her on the other side of the room would be helpful in preventing cheap deaths to an unblockable three damage.