I want to make a small 500-1000pt list of mordant acid dogs and need some help with making it fluffy.I have some ideas but I need help with units and creating a fitting regimental doctrine.

Lore wise the regiment is made up of criminals and thugs who live on this mining world,Mordant.The surface is inhospitable,so they all live underground and mine for this acid that's used as ammo for Hellhound chem cannons.They specialize in tunnel fighting and are know for stealing equipment.They also hate mutants.

Obviously hellhounds are a must,no flying units or abhumans,lots of special weapons,and atleast one comissar.Probably going with brutal strength and veteran guerillas for the doctrine,but ehat do you guys think?