fluffybunbunkittens
Hero
Yes. Barbarians are already limited in their number of daily rages, so it's definitely kept on a short leash. But, because Rage gives you advantage on Str checks, and Primal Knowledge turns a few skills into Str checks, the combo of using higher stat + advantage is pretty hefty for when you do want it.Enter a rage and continuously extend it with your bonus action, for up to 10 minutes?
The default way of using both to your advantage would be to Rage first, then stealth into combat, which certainly gives Barbarians a niche, but definitely might not fit a lot of concepts. Surprise becomes the middle name of orc barbarian hordes, kind of a thing.