How about a heal bot? floating probe that heals like the MP has usfull even if it only heals the pet.
Not sure but i think engineer is the only pet class extreamly dependant on that pet, MP have some nukes and crats have charm and nice nukes.
Or how about give engineers the ability to summon weapons for pets? that way the option is there and it adds to wanting them in teams for heal bot and summon weapons/ armor. The weapons should be able to be held by other pets or people....sometimes i am sure i wouldnt want my pet to have ranged .

(crat pet sometimes rushes to attack a mob you just calmed...with melee it gives me a chance to pull it back before it hits)

Fixers have those summon armor and weapon nanos but no one really uses them as far as i have seen.
(except Grid armor)