I think it would be really cool to have a statistics report for each round -- just in a spot in the menu if you want to look at it, not like you have to look at it. Like here is the number of pops for each tower to see which towers really are worth it toward the end of levels. Great game!
 "Bloons Tower Defense 4"){kind=icon}
 "The Enchanted Cave"){kind=icon}
 "I Am An Insane Rogue AI"){kind=icon}