I have suggestion. Maybe you could impliment a second layout for upgrading Heroes. You could put the hero avatars mit Level and upgrading cost without dps and skill details side by side to each other that you dont have to scroll up and down the hole time to find the cheapest one.
Understand what I mean? Sorry, my english is not the best. But really awesome game! Really! Thank you!
 "Slurpy Derpy Classic"){kind=icon}
 "Shonen Idle"){kind=icon}
 "Tap Tap Infinity"){kind=icon}
 "Idle Empire 2"){kind=icon}
 "Idleplex"){kind=icon}