I like the flavor of this but feel PAM is still abit better as the bonus attack will always be there. With this, you substitute your attack which would be very situational and rarely used when a class gets two attacks.
Yeah, the Barrage feature is likely not as good as PAM bonus attack, but it might be better for some (classes without Extra Attack, or classes that have a lot of competition for bonus actions). So I'm okay with that, I think (though I'm open to tweaks).