But Battle classes should be taken into account. They (along with Crafters) get insane amounts of SP in comparison to Gatherers. Outside of leves the gathering SP is outright awful and then adding two kinds of fatigue, forget it.

Gatherers should be able to gain comparable levels of SP from their actions in comparison to both battle and crafting classes. Crafters get their own set of leves but Gatherers have to give up Battlecraft leves if they'd rather gather.