well finished it in like 10-15 min,
good idea, some balancing and more content and it will be gold
only thing that bothered is that upgrades show what it will be so at beggining we see base value 2 but we get 1 when it passes to exit and when we buy gate 1 it says x1.5 when first upgrade is x1.25. so if you are out of this project then for next consider to make values that are going on more clear just show current number so it do not confuse ppl by seeing base value 2 and getting 1 for each pass then after buing gate 1 you see x1.5 multi and it gives between 1.2-1.3 (coz of rounding from 1.25) or separately show base value and how it changes with upgrade base value:1 (x2 for $100)