maybe have one that applies a move speed debuff. ( useful in pvp.)
also do what you did with bio chem and lets make the purples reusable's so that only those who specced into armstech can use them. (better if you don't imho.)
you could also let arms techs create one shot consumables such as the http://starwars.wikia.com/wiki/Stokhli_spray_stick.
(again useful in pvp for when your main stun is on cd.)