weary tinsel
Do you really expect players to grind for hours or even days with Mickey just to unlock a new character when the game goes Free-2-Play?
Suggestion: If you intend on keeping the Shard system, then make it so that the FIRST shard that a player collects unlocks that character.
It won't undermine the Star Tiers for the racer's strength. If anything, it will just encourage it. Can you imagine the excitement of unlocking Figment or Stitch and then seeing that the two extra Racer Shards are there for the next Star Tier?
rich trout