Thanks for these suggestions. They're very good and I'd be likely to implement them in an update. :D
As for whether or not it's infinite, it's not. There's a bar on the left of the UI that shows you how far down you are and how close you are to the end. After you've beaten the game, there's an option to play to infinite depths. The end is at 3000m. (It gets pretty crazy in the 2000s.)