Yeah so I think speeding up the gameplay a little bit (i.e. the movement speed & jump height) would make it feel a lot more satisfying to play. A lot of times with platformers its best to try to avoid slow movement unless its for a distinct purpose. I also noticed that a lot of the walls were kind of "sticky" so like you could jump into them and you'd stay there. I'm not sure if this was intentional or not, but if not in Unity you can create a 2D physics material and set "Friction" to 0 and then apply that to any platform colliders and that should solve that.
I also think it would look a little nicer if there weren't the little gaps between the tiles. I've also had that issue in the past but there are a bunch of good resources out there to fix that issue. Unity's tile map system is very powerful!
Other than those few things its honestly a pretty solid game! You included a lot of polish details that a lot of people miss like particle effects while running and jumping that I really appreciate seeing in such a short term jam. Good job you should be proud!