My title is a little misleading, but the problem I’m solving is capping the unhappiness of P2W players who’ve dropped hundreds of dollars to fail to obtain one specific event/HOTM hero. My solution comes from another game I played, Pokemon Duel.
The idea was you spend your gems on summons and every summon you do you are given a hero AND 50 Material. Over time you accumulate Material and eventually you can buy a specific hero from the Shop for some amount of Material. In Pokemon Duel as a F2P player to save up enough Material for a 5* figure it would take 4+ months.
Maybe a similar system could be implemented for E&P. This would make the amount of money a player would need to invest to obtain specific hero finite. I think it would make a lot of people happy while still allowing SG to take in a few hundred dollars from the P2W players. The only downside is it might limit the incentive for any players to gamble thousands for a single hero.