I was looking at the Lemonade Stand Wiki and one of the wishlist items is "Random events that may influence supplies and/or cost and/or customers."
One idea I came up with is having sales on items that are needed to create the lemonade. The sample I created shows an example of a sale on lemons making them $0.25 instead of the usual $0.35. I think that this could add an extra element to the game in that a user will have to think more about when to buy particular ingredients. I noticed that there is currently a feature in the game where items "decay" after a certain period of time (I believe 5 days) so this would require the user to think about how much they should buy based on current price and anticipated sales. A small note with the decay feature is that I think it should be announced to the user when items decay because it took a while to even realize that it was happening.
I think I want my primary focus to be implementing a better system of counting money but adding more events also seems feasible especially if someone else would like to help me with the coding.