Thank your for your super complete feedback!
First I'm glad you enjoyed the game.
For the UI you are right and it will be the first thing I will fix on a more polished version of the game 👍
I agree the art is inconsistent, it's just that I was alone and not that great at pixel art so I used a lot of free assets (I could have done every assets myself but the game would have been a bit empty since it already took me a lot of time to make the gameplay good) But I agree with you so myself I wouldn't put 5 stars on presentation lol. It will be improved if i do a post-jam version.
And for the glitch yeah it's a funny bug that will maybe become a feature, who knows 🙄
For the health you can see you character color changing when you are losing HP but yeah I can make it more clear if I add a health bar somewhere. That's also planed if a more polished version see the day.
Wow, I'm super happy you played through all the game! Yes the final level was intented to be a bit harder, and the higher your score goes on a level the higher the difficulty is, having a super high score on the first level can make it incredibly hard for exemple.
If I make a full version there will be an endless mod, that's 100% sure!