Difficulty had to have been the aim here. But that is no excuse for the programing flaws.
1. Character speed was hit or miss. on time you'll tap the right arrow he'll barely budge. Tap the left arrow to stop him and he speeds away like he's on drugs. This especially applies to the slick ice.
2. Wall jumps were also rather hit or miss and were very frustrating, as the character might jump at an angle or straight up because you have to hold the left or right arrow key towards the wall you want to kick off of.
3. I'm going to place this under collisions. When you hit your head while jumping regardless of what speed you are going you might come to a dead stop and fall to your death.
4. The camera man was an interesting idea, executed poorly. On certain levels he covers up the one block of ice you need to land on and you can't see it until it's just about too late. It also doesn't make sense. Your character can't tell if a block of ice is real or not?
Taking this into consideration, I'll give you a two.