cant divide them into more slots atm. body armor is one piece only chest and pants because there is only one slot on the character for it.
I guess we will need to wait and see what TFP do for clothes in general in the future.
You can change the armors models and xmls but keeping that in mind, its 4 slots only, so head, feet, body, hands.
Im having a ton of work atm, so im trying as i can to do the vanilla armors variations, without going crazy on it. but we have tested fully custom models and it works so in the future other things would be added. not sure if me but maybe some other modder picks up and does more stuff.