I feel like these enemies like Chickenauts, Slobs and armored achickens are not so strong in hard/elite difficulity missions, so this idea will let 'em become stronger.
They will shoot more bullets when the difficulity is getting harder:
Chickenauts: 4 Bullets at once when 80%-90%; 5 bullets when 91%-100%
Armored: 4 Bullets at once when 80%-90%; 5 bullets when 91%-100%
Slob: 13 Bullets at once when 80%-90%; 14 bullets when 91%-100%