I'd rather nerf the healing, by having the yellow and green beams heal less than they do currently when the target ally is not in repair mode and not heal the user unless the special abilty is active. The special ability should, in addition of repairing the target ally faster, remove any ailment (decreased defense, emp, ism, whatever Mamabear inflicts) on the target ally and increase the amount of damage dealt to enemies by the user's red beam (i think it only increases the selfrepair speed right now.
The tracking ability should stay, so that the technician can use its lefthanded weapon against enemies, while still healing the ally. Manual aim for connecting the beam with the target and then sticking to it until deactivation might work, maybe.
Another idea i have, to emphasize the technician's support role, modify the lefthanded weapons (aside from the redox rifle):
The technicians Hawkins-RPR should deal less damage, but inflict a "tank leak" ailment, meaning that fuel is slowly decreased (effectively slowing down fuel regeneration and increasing the cost of boosting and flight).
That bright red gun should inflict whatever Mamabear inflicts on targets. Adjust damage if necessary.