@Sirrian, a humble proposal to make her fun, thematic, and balanced:
Extra Turn and:
Fizzbang- Explode 2 random Green gems. Buff an ally, as current.
OR
Misfire- Explode all Green gems, and burn 2 allies.
This has risk, reward, and a reasonable amount of mana gain no matter which result occurs.
With your current nerf, getting the buff is pretty unrewarding, as most likely it will not hit a useful troop/stat. Getting 5 to 12 mana from the 2 explosions is a good consolation prize.
On the other hand, getting an all Green explode and an extra turn is a powerful effect. Burning allies isn’t enough to make this unusable, but it is a minor and thematically appropriate drawback.