I have been playing the game for a while and I think the devs did a great job on bringing some of the core mechanics from D&D to a mobile game. I got it that gold is the way the they’ve chosen to pace the game progression. I don’t mind that, but I feel that free challenge and free chest are not rewarding enough when coming back to the game.
I would suggest some other game mode where players can assign the heroes to quests/missions with different requirements, duration and rewards, allowing the players to plan their game sessions and giving more reason to come back to the game. Missions could even have simple interactions like making decisions or some dice rolling.