So... I'm in the starter city. Seems like the best farming location I can find is the tunnel with the bat dragon things. Which are up to level 7.
Which kinda doesn't actually move the needle on xp. It's nearly 15 minutes to grind one level.
I've kind of just lost any interest in doing any of that. But my pokemon aren't strong enough to progress the story.
I'm hoping that this is just me being ignorant of the obvious place to farm, and not a case of this game making Tem Tem's grind seem to zoom along.