The gameplay, visuals and overall mood are all spot on and feel really great. I really enjoy how the mechanics all play off together and provide a very expansive set of tools to play with.
That said, I felt that the early levels didn't really cultivate within me the want to really experiment with those great foundations. Instead it seemed more optimal to race through with the vignette on high parrying and slicing away.
In that way maybe focusing the early levels a little more could help to encourage players like me to really explore the great set of systems you've built.
But if you nail that progression, I can't help but think these mechanics would make a great little indie.