+1
Especially for
I think, Berserkers specifically (not other classes or even other Barbarians) should have the ability to remove a level of exhaustion with short or long rests, not just long rests. That still means you are limited in how often you can use frenzy (2 shor rests per long rest, but up to 5 uses of frenzy), and especially limits how often you can use it consecutively in dungeon crawls. So the idea behind the subclass feature is still intact, it is just not as crippling for the subclass.