Bleach updates
The premise could be good, but not by having straight up fights against monsters. Humans should be cheating bastards who exploit their advantages of tools, numbers, and coordination. The way to kill vampires is not powered armor, it's a Firetruck.
A direct fight against monsters is what the monsters are best at. So cheat. Use mines, bombs, toxins, snipers, etc. . . That's the way to beat the monsters, not by simply getting stronger than them.