I did see some close post saying : "add a head slot".
That's true, it would be more useful to add more body slot overall. The fact that some of the item we can equip in this slot are trigerred by the jump button (jetpack or parachute) might make it hard to do so ( or at least it's what made me think "that's why there's only one of this slot" ) but well if you equip one you souldn't need the other.
But since some monke... hmm... players will try to equip both of them, at least yes, add other body part slot like the head and the back (for the gas mask and for the jetpack or the parachute) like that we can enjoy the blade runners that give us more mobility on ground, the protection of the gas mask and the air mobility/security provided by the jet pack/parachute.
Continue your hard work, your game is truly awesome.