It's not a bad idea. Still, the execution... the game is cool and all, and there's a lot of effort put into it and you can tell, different heroes, upgrades and so on. But the gameplay reduces to basically selecting the heroes, maxing them as you gain coins, activating the bottom center powerups (BTW, there are no tooltip so I can only guess what they are and what they do) and if you die, just keep upgrading until you win. There's no challenge or strategy, I'm sure if you choose some heroes over the others you'll finish the round a bit faster but you'll still win because you'll eventually upgrade enough.

The gameplay is my main concern, the game looks awesome and the progression and hero unlocking is really well done, but unfortunately the dungeons felt too repetitive and I didn't even care which enemies or heroes I had, I knew I'd eventually click enough upgrades that I'd win.

I'd probably change it for less enemies (like 2 or 3 per room), a limited amount of lives and THEN heroes, upgrades and powers will make more sense since you'll strategically need to use an ice power against a fire enemy, or magic against an armored enemy and so on.

Hope it helps!