Personally i was a bit late on the mood-scroll bandwagon i was so busy putting all my contributions into group skills that when i finely got them all to level 50 Group summon came out.
I think that once a group reaches level 10 or even 11+ the Shape shifting card can go.
To be honest i don't see a whole lot of people using them at least not every single day i think Shape-Shifting cards if they are going to be earned from anywhere should be the online pack you get every day.
I also don't see why they put it in the shop for the price that it is seems a bit pointless to me.
I'd like to see them update the group wheel to remove shape shifting cards move them over to the online pack and then everybody is happy.