Double posting because this is totally important.

Light was a complete joke, most likely due to the insane Dark Grid the game has thrown at us so far.
Wind was quite scary - second boss Rage Overdrive slams you for 7k AoE even with elemental advantage. Now, I can take one of those easily, maybe even two... but that's still not the kind of damage I want to see happen every few turns. I cleared Wind quite easily, but I am certainly not the average Fire player due to Belial and an insane Fire team. The lack of a proper F2P Fire Grid might topple people on this one.

Drops wise, you basically just get an extra plat box. So it kinda doubles your Accessory progress since the bottleneck is actually finding useful SSRs.