The eidolon drop rate just seems really low. After 3.1mil PP and 90/149 blue/red medallions, I've gotten 3 of the SSR weapon from Gatcha and only 1 SSR eidolon. Since I usually MVP or sub-MVP, and the platinum chests seem to be random-color tickets, the ticket balance wasn't off as much as the medallion count suggests.
Having to farrm 4mil PP is a pain. Didn't really want to have to do this. In past events I'd maxed the eidolon by this point.