As a response to the shards thing, I think its a good opportunity to reward/compensate players in a better way. Instead of getting Premium Relics or theonite for any sort of extended maintenance that may have resulted in a lost Gold from PFs, you could get x amount of gold shards. Its a pretty specific example but I'm just trying to highlight the benefits of switching from % to physical shards. I do agree with you to a degree about the extra currency thing though, although I wouldn't call the elemental shards currency, they're more akin to materials from other games. Skullgirls Mobile was a really simple game to get into, the UI was easy to navigate and everything was well explained. As features increase the game may turn away new players due to being too complex. I don't think this new feature will contribute too much as its strictly late game, but its an issue to keep an eye out for.