I understand that F1 used to be both berserk activation and burst skill and now F1 is core burst, F2 is entering berserk mode and F1 in berserk mode being an elite burst.
But I just don't like this flow, I guess design-wise you are right and moving core burst to F2, berserk to F1 and elite burst to F1 as well would be odd, but oh well, I just simply dislike this flow change, it feels too different and unpleasant.
I see that some players like this change, some don't, so it's not so one sided to say one is objectively better than the other.
But oh well, I personally would rather try to main Bladesworn now or switch to Condi Vrituoso, with the way it's now Power Berserker is dead to me.