I had quite a bit of fun with it! My suggestion would be to remove mouse for retry. Only using spacebar is really great, and would be nice for that as well.
The slope felt kind of empty, which could be fixed by giving the player a slight break, and adding a few 'checkpoint' props. (A cabin at 100m, a ski lift at 200m, etc.). This would also help give a sense of progression outside the leaderboard.
Overall really good job though! The main loop, and competition from the leaderboard is addicting! :)