My shit Ideas:
A crayon that lets you make your items mimic others in appearance and desc(Emag looking like a regular id, ebow looks like a toy one, etc). Turns to ashes when done.
Demotix cartridges being able to poison, stun or just straight bomb the person as usual.
Explosive implants that you can inject in yourself or others to encourage them to listen to you. More implants in general really.
A gun that can load shotgun bullets(Shotgun bullets can do many things such as set people on fire or bullets filled with mutagen) or just different types of bolts for the ebow.
A headset key that lets you hear all comms.
Make those now useless sleepy pens refillable.
Stun gloves.

A item that lets you booby trap almost anything (a id, gloves, computer console).
Emags not having any limit on what they can fuck up (Emag a camera to turn it off for a minute, emag a person's head to deactive their headset, emagged vending machine makes it come alive(Maybe too OP), or just emagging the gun to make it malfunction and give a short beepsky smash like stun.)