Borderlands 3 should have a Vault Hunter based on a loader bot, with an action skill resembling expendable assets but dictated by the skill trees you pick more so than the doppelgangers. A melee skill tree based around the concept of regular loader bots and hyperion engineers with the summoned loaders turning into bul loaders, a gun focused gun loader tree based around summoning gun loaders and dealing gun damage, and an exp loader build focused on summoning exp loaders and using torgue and tediore weapons to maximize grenade damage while having exp loaders fight for you. Maybe a fire skill tree with HOT loaders, perhaps a support tree with repair surveyors similar to Wolf and Saint, obviously there is a massive amount of possibilities for a new robot character based around such a diverse enemy type.