Very straightforward mod that adds the utility item slot to the light and heavy armor sets for any armor tier that allows it for medium armors.

Slightly unbalancing, but grenades are fun.

Version history:
v1.2: updated mod to latest patch 3/10 (can't find the version number...)

v1.0: initial release

To clarify some confusion about this mod: 
This does NOT add the extra utility slot to Kevlar. Kevlar is the first tier medium armor, and vanilla XCOM2 doesn't have the utility slot on it. 

After Kevlar, all higher tiers of armor work like this in vanilla: 

Medium: grants bonus utility slot and only needs to be crafted once for infinite sets of armor 
Light: grants movement bonus and one or more special abilities (for ex: grapple), needs to be crafted one by one 
Heavy: grants bonus armor and one or more special attacks (for ex: rocket launcher), needs to be crafted one by one. 

This mod changes ONLY the Light and Heavy armors to also grant the bonus utility slot.