This sounds like a good and noble pursuit, but I would be able to take exactly one ghosting or premature rejection before abandoning it completely. There are so many BS reasons applications are ignored, I can’t see this approach working well. Maybe if you can network your way to a manager or something
There are no foolproof methods. Shotgunning makes it much harder to get past the recruiter screen. Yes the high touch method leads to larger feelings of rejection but its also more likely to actually work.
