If i could change one thing it would be to implement a system similar to hearthstone.
Every hero in the game is available to get without rng while rng still prevails in the game. You can exchange cards/heroes you don’t want or just have duplicates of for “dust”. Then you can use this dust as a currency to buy whatever hero you want.
Obviously there would need to be a balanced system in place for how much dust you get for exchanging heroes and how much dust is needed to buy heroes. Whales could buy more dust to keep the money flowing, people would be more engaged to work up to buying a hero they actually want instead of spending months for a big pull only for all that work to be wasted on a bunch of 3* dups you’ll never use.