First off I think that allowing us to use Spacebar to jump would be a great improvement, and also please add a way to restart the level when you die (Without having to close and reopen the game :D)
Just played it, feels much better already ! 2 things though:
1. You should probably add an Area2D that kills the player when they fall into a pit, because right now I have to close and reopen the game (Unless there already is an Area2D, then in that case you should probably make it closer to the pit)
2. I get the feeling that the dash is too short + lacks some juice, just personal opinion though.