This is why I'm suggesting this. Before you could accumulate a large amount of Spirtstones and choose which Hero you wanted to free. Now, Every Hero needs it's own individual shard and I think, in trying to make the game more challenging, the developers went a bit over the top on this one. Even if I focus on playing just one world in hopes of gathering enough shards for the one hero I want to upgrade, there's no way I"ll be able to do that for months and months. I think I've gotten 3 of the one I want since the change over...I need 150. I think if they were changed to Elements, we could at least say, collect 100 Fire Shards and chose which Fire Hero to use them on. It would still be a challenge, but at least we'd be able to have some hope of achieving the goal.
I really hope you'll consider this one!!