First off I feel like there should be an actual block button instead of it happening automatically. Blocking feels inconsistent which is unacceptable in a 1-hit kill setting. I've taken attacks head on where the block should have triggered, but then also blocked attacks that looked like they should have too far to the side to stop. An actual block button would make controls feel more solid and add a level of skill difficulty to the game. Arrows are also too easy to counter as is and manual blocking would help this some. Right-Mouse is the obvious choice here.
I'm not really a fan of having to swap between sword and bow, if only because I can't remap keys to change switch bow and sword around (old habits from other games are hard to break). Since Right-Mouse is (hopefully :P) going to become a block button, I would like to see Left-Shift become a keybind for the bow. Hold Shift to aim, then you can still use the Right/Left-Mouse for the vertical and horizontal arrows that already exist in game. Should probably add a Shift Toggle option for the Bow too for people who wouldn't want to hold it instead. Some might say that this would make the game easier now because swapping to bow adds the risk of not being able to block arrows or swords, but I think manual blocking would even that out.
Horizontal attacks are another place where controls feel a bit weird. In short, I think there should be an option to reverse attack directions. Currently, moving right with D and attacking causes the sword to swing from right to left, meaning in 3-D space, the sword kind of sits stationary as it moves towards the spot you just came from as opposed to slashing across the area you're moving though. I my mind, this just feel more intuitive, but others are probably already use to the current controls, so I would just ask it as another option.
Overall, this game is a lot of fun, great way to kill an hour or two, it'll be interesting to see how it develops.
p.,s. be sure to thank everynightxRIOT on youtube, he's the reason I found this game.