I am loving this and can't wait for a full release. This is the type of h-game I wish I could find more of.
So, yes, as people have said, hitboxes are a little bit wonky at times, and thought I would note a bug I encountered. End of the first screen in the ruins, the slime attack speed is just the right speed to knock you down from jumping to the ledge. That's fine. The bug was when it attacked me and pushed me into the seam between the slime platform and the one above, it made me fall to my death.
Hey, I expect bugs worse than this in AAA titles, so please be assured I love the game!