For the FREE CHEST you get every 4 hours, why not offer players a choice from one of four chests, where each chest only gives you gear for a specific character type - Sturdy, Mighty, Skilled, or Tough.
That way, instead of getting gear from a pool of 8-13 heroes, you’re only getting gear for 3-4 heroes and have a higher chance of getting stuff you might want.
Wouldn’t be hard to implement and wouldn’t change much overall in the game state since it’s a time-based reward with limited chance for high rarity gear.
Input?