Strafe fires something like 4 Hungering Arrows a second, you can fire two more manually a second for a total of 6 shots. That’s without going into breakpoints, Valla’s, Rocket Storm and those kind of things that can get you between 7 and 8 shots a second when all totaled with manual and strafe’s automatic shots.
But yes, all the shots do the same amount of damage.
If you want to get into the ins and outs of how GoD 4 piece and breakpoints work and how Valla’s and/or Rocket Storm work together there’s some threads you might want to look into.
Are a good start.
This one is also worth a read for it describes how area damage and Devouring Arrow work together.