I wonder if Vlad, Human Hunter by Enigma wouldn't be a great fit? He's sort of lithe like drukhari but also kinda bulked up by his armor. Plus, at 32mm scale, he'd be a head taller than your war boys.
*That hellion's face is perfect. Could you GS the hair? Might help to bury the hellion head beneath a mane of hair in order for it to not appear out of place on Vlad's shoulders.
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