At some point there's not much to do and no real way to progress. There are a limited number of quest slots, so increasing the number of heroes on quest is impossible, and the remaining ones have to be bankers.
Also the items don't scale their powers. Since all that matters is how much extra "ability power" you get for your bankers, and that is maxed at 10% and only depends on the rarity, not lvl. making it possible to gather using low lvl quests as well.
So... what's the point of playing later in-game?
 "Questmore"){kind=icon}
 "Idle Evolution"){kind=icon}
 "Puzzle Fuzz: Idle Stories"){kind=icon}
 "Witch Hunt"){kind=icon}
 "Go Go Goblin 2"){kind=icon}
 "Auto-Attack!"){kind=icon}
 "Idle Farmer"){kind=icon}
 "Clicker Heroes"){kind=icon}
 "DPS Idle"){kind=icon}
 "Decision:Medieval"){kind=icon}