I feel like Blizz can keep their store in place where you can still buy premium skins, but there should be a way to earn them to.
Bring back the old lootbox system, put these ‘premium’ skins in the lootbox pool. Give us currencies for duplicates again and if someone doesn’t have the patience or want to grind out lootboxes to get the skins or currencies for the skins, they can just straight up spend money to buy currency to outright buy the skin. Simple.