How about allowing engineers to remote control their pets? like making nano that connects caster with their pet and makes it posibble to control em directly, but at the same time makes it imposibble for caster to move while nano is active.. and drains bit nanos to keep link active...
Or making it posibble to create engineer usable robot armour that could boost armour class of the user and add some good boosts to certain skills, like martial arts, brawl and increasing physic int? making engineer considerable fighting machine... but at the same time, limiting engineers abilities to use nanos, healing kits and stims... and making armour only take certain amount of hits before it gets broken when engineer has to make another one (via nanos)...