I just came from playing the demo and I really enjoyed the art style, although there were a couple gameplay issues that made the game more frustrating than enjoyable. I have no idea what goes into making or coding a game like this so I'm not sure how many of these observations you can fix, so I'm just going to state what I felt needed to be changed. (I apologise, this could get a bit long)
The first thing I noticed was the controls. I played it on an Xbox One controller plugged into my computer so I don't know if the problem was on my end, but there was a small bit of delay between hitting the buttons and executing the action. It wasn't much, but it did cost me a couple of lives, especially when trying to parry some of the enemie's moves, especially the mountain goat. If it is on my end, I suggest instead having a dedicated button to parrying instead of using the movement stick plus attack. I often found myself moving left or right when I wanted to parry and it allowed enemies to hit me.
Another thing I found was that once I attacked, I was locked into the animation and I couldn't move or roll when I was attacking. This is just personal preference, but I think the combat would be better if you were able to instantly roll in the middle of an attack, even if the attack didn't land or do damage. Again, that was just personal preference, the game played fine as it was.
The second thing I found was that the enemies were a little hard for first level enemies. The hedgehog and the wolverine were fine, I had no problems with their difficulty, It was mostly with the mountain goat. With the controls as they were, it was very difficult to time and I lost more than a few lives to them. Perhaps slowing their speed will allow new players to learn the controls and the types of patterns enemies will have.
The boss fight was fairly difficult mostly because I could not dodge the cross-screen bookcase attack due to the flying book that would hurt me and stop me from reaching the safe space in time. It was hard to hit the book since it was so fast and, in the end, I died six times before defeating the boss because of it. Other than that, I had no problems with it.
Despite it's flaws, I found the game extremely beautiful and fun. The character designs were unique, fun and memorable. The dialogue was very well presented (and I particularly enjoyed the song in the tavern). Wilhelm was one of my favourite characters, I believe he can be a batter one day. I absolutely loved the art style and the way the intro told you a quick summary of the world around you was fantastic. I was invested in the story and was super sad when the demo ended. I will most definitely be buying the game once it comes out completely!I loved it! 4/5
Edit: I saw this game at SMASH in Sydney, Australia and was immediately interested!