Don't use unity's built in physics for platformers please. Also, make sure you add coyote time to your ground checks.

Yeah just echoing what other people are saying at this point. Cute game, but you want precision platforming out of your player when the character can't be controlled very well. The ice physics have no indication of how fast or slow you will slide when you land, nor when you jump how high or low you will go. Really do like a lot about this, and it looks like you put a lot of work into it. It just doesn't pan out in execution.

kinda good, the levels become too hard to fast, and the player slides when he lands which I don't think is good.

Speed is far too high, making it pretty uncontrolable in many levels.

I agree with greep321 here, the max speed is high and the character accelerates faster than a rocket