My used gems: 9000
My current gems: 3180
Gems I can still obtain from co-op missions: 420
I've played since the very beginning and missed 30 gems as a daily on the second day.
Duplicates: 9 (assuming 9 unique characters including Kris, I would have another 150 gems from sync pair stories)
Subtotal: 3780 current gems = 12 more rolls = JUST hitting all 65 characters = 120 more gems
Max Potential: 12,900 potential gems (43 rolls) in 40 days, with probably less than 300 left between completable achievements. If you could somehow keep resetting your rolls so you got a new character every time, you'd have enough as of today to have obtained all 22 story characters, Whitney, and the next 42 characters that need to be rolled and STILL have enough leftover for rolling Blue tomorrow (though you'd be getting another 230 tomorrow anyway).
